• Creating classes
• Creating an interface
• Implementing an interface
• Using a magic constant

Here’s the video,

Make sure to take the jump if you want to see the final source code!

Here’s the source code

Mainly, the important concepts are:

• Using an interface to identify objects in an array
• Using instanceof to determine this identity
• Using a magic constant to do cool stuff
• Using an array to hold objects

I feel that the two things discuss from here on is what an interface is, and a little about magic constants.

Interfaces

Interfaces as defined by php.net are

Object interfaces allow you to create code which specifies which methods a class must implement, without having to define how these methods are handled.
Interfaces are defined using the interface keyword, in the same way as a standard class, but without any of the methods having their contents defined.
All methods declared in an interface must be public, this is the nature of an interface.

So again, Interfaces do not have code, they only have public functions which implementing classes must, well, implement.
These are great when you want another coder to create the implementation while you work on how things use it.

You may take it like this, Lets say you are creating a transportation grid, you say that a basic vehicle needs to be able to start, stop, drive, turn, and change speed. You don’t care what these objects are, as long as they follow these rules. Your worry is making the grid work, and these vehicles, are more or less cogs and gears which fit your standard.

Magic Constants

Magic constants are constants in your code that you do not define, and PHP does based on context.
There are multiple, useful constants which you can use.

• __LINE__
• __FILE__
• __DIR__
• __FUNCTION__
• __CLASS__
• __METHOD__
• __NAMESPACE__

You are welcome to visit the above link to see the description for each of these magic constants, but basically, they are helpful, at least in my experience with debugging and logging.

Well, that’s the end of this tutorial, I hope you enjoyed it!

• Class creation
• Class Extension
• Peak into the static keyword
• Example of instanceof
• Small explanation of the self keyword

Here’s the video, I’m totally winging it without any prior planning other than to cover something more that I did not cover in the last tutorial. Thanks to you subscribers now, I don’t have to split up my tutorials!

Make sure to take the jump if you want to see the resulting source code and textual explanations.

Here’s the final source code

So, lets break this down to what everything means.

We first make a bank, and an account class.
The idea here is that the bank holds accounts. The bank has the methods(functions) addAccount and getAccountFromID to respectively add account objects, and retrieve account objects.
In our account object, we have a means to modify the money value, and to retrieve the current value of the account. Also, to ensure every account has a different ID in this code’s execution(one page view, run, what ever you want to call it), we use an incrementing static variable, which is private to the account, meaning outside this account class, nothing can modify it(which is good, unlike a public variable, which can be modified anywhere).
We also have this specialAccount, I have not overridden any of the functions in the normal account class, I can, but I simply wanted to show inheritance today. This specialAccount class retains all the functionality of the account class, can be identified as an account, but can be separated or distinguished by being a special account, which may be detected (true, being “yes it is”, false being “nope”) with instanceof compare operator.

So, to put it to an example with birds, I may say that there is some class, or classification to pun it like that, I have a bird class, and this theoretical bird object can do the following
Eat, Sleep, Procreate, all inherited from some generic animal class, however it can also fly, so I make a bird class that extends animal, and I make flying functionality.
So then I can be even more specific and make a dove and raven class.
there’s no real difference except for I guess color, white and black.
But, programmatically, I won’t be differentiating based on color, as there might be an albino pigeon somewhere., so I will be differentiating using what their instance is
if I say return $dove instanceof dove, I get true, if I say return $dove instanceof bird, I get true. However, If I say, return $dove instanceof raven, I would get false, even though raven is a bird.
So instanceof will return true on the class it came from, and all of the parent classes or interfaces that it came from.

Now back to what I’m making here, I also use the self keyword, it is like $this, which returns the current instance, but the self keyword points out this class in a static(non-instanced) sense.
You may take it like this, you have a phone, it has serial number, than serial number came from a static reference when it needed to be made. Static things are also great when you need to just do a basic function that you don’t need to use any per-instance variables in, so really it is a parameters in, stuff comes out kind of function, but appended to a class name for further identification.

I feel that the rest of the code explains itself, however the 85th line called “Is account 3 a …”, the parameter should be changed to 2, it is 2 because the static account IDs start at 0, and the third account created leaves the id trail to be 0,1,2; so as 2 is the third created, it is called the third account. I however changed that to 1 to show that a normal account returns false, as opposed to a preferred account, which is recognized.

Make sure to post your questions below, I will get back to you on them.

• classes
• public/private variables and methods
• magic methods
• method chaining

I use a diagram to show the concept visually before creating the code, and then I test it in the terminal.
I also show variable casting to ensure that information is properly handled, even when it is of the wrong type.

So here is the diagram of what I am trying to get accomplished.

I have a ‘some class’ that has two methods and two variables. This diagram does not include the function tri(), that I introduced by improvisation (as always) into my tutorial. Furthermore, the result of foo() in some class is an object as defined as ‘other class’. From this I can chain link and use the zed function.

I also introduced the magic method __construct() which activates on the object creation depending on the class. Just refer to the diagram as needed to understand how things are linked together. I hope my video will convey to you in greater detail of what is happening with this setup.

And now the source code!

 1 <?php
 2 //Object Oriented Programming
 3 //http://php.net/manual/en/language.oop5.php
 4 class some {
 5     private $z;
 6     private $a;
 7     public function foo(){
 8         return new other($this->a, $this->f);
 9     }
10     public function bar(){
11         $beans = $this->a;
12         return $beans*4;
13     }
14     public function tri(){
15         $this->a++;
16         return $this;
17     }
18     public function  __construct() {
19         $this->a = 3;
20         $this->z = "I like chocolate milk";
21     }
22 }
23 class other {
24     private $e, $f,$g;
25     public function zed(){
26         return $this->e*$this->g;
27     }
28     public function  __construct($e, $f) {
29         $this->e = (real)$e;
30         $this->f = (real)$f;
31         $this->g = ((real)$f+1)*10;
32     }
33 }
34
35 $something = new some();
36 echo $something->tri()->tri()->foo()->zed();
37 //echo $something->foo()->zed();
38 echo "\n";
39 ?>

In the next tutorial, I will try to show a practical example with an bank.
And here is the source code in a zip.

Next, the forms that submit data have to be modified to accommodate the character set(for some reason PHP or the browser gets it wrong and it turns into a mess.
If you set the attribute in the <form> tag

accept-charset=”UTF-8″

It should send to the server correctly.

SO… like <form accept-charset=”UTF-8″ action=”blah.php” method=”post”>…..</form>

Also, to make sure it displays correctly on the page, wrap it with iconv( ‘UTF-8′, ‘UTF-8′,$row['title']); or mb_convert_encoding($row['title'], ‘UTF-8′ );
However, I noticed it doesn’t like htmlentities wrapped around it or anything like utf8_encode, or what ever. So be sure to test!

Have fun

• Implement the Fancy Editor into posting
• Create a way to edit based on the posting

Now, it doesn’t sound like that is much to do, but as I explain it in depth, you will understand that there is more process to such implementation than what two bullet points can convey.
So, here is the recording(total ~ 25 minutes), there are two parts so please make sure you click on Read More to see the download-able sources along with part 2.

At this point the blog system has the ability to show all the posts in order of date of modification/post, to show posts individually, and to make new dull plain-text posts… That’s about it.
So, first you can get CKEditor(not included in my sources download), so get it here and proceed.

If you wish to get the sources before all the modification was done on this tutorial, please go to PHP MySQL Tutorial 13: Posing on a blog and download the sources as provided at the bottom, so that you may be able to code with me step by step.

Now that we have that business taken care of, we need to proceed and make the modifications.
The first step is that we need to look at one of the samples on how to implement the CKEditor. You may see one under ckeditor/_samples/php/ in the ckedior download. I happened to select the “advanced.php” that has extra settings like width and height.
From there, I simply copied the sources that initiated the ckeditor class and presented the code into put.php

   1    <?php
   2    include(“connect.php”);
   3    if(isset($_POST['sub'])){
   4        $title = stripslashes(trim($_POST['title']));
   5        $content = stripslashes(trim($_POST['content']));
   6        $title2 = $title;
   7        $content2 = $content;
   8        $error = false;
   9        $reason = ”;
  10        if(strlen($title) < 3){
  11            $error = true;
  12            $reason .= “Bad Title.\n”;
  13        }
  14        if(strlen($content) < 3){
  15            $error = true;
  16            $reason .= “Bad Post Content.\n”;
  17        }
  18        if(!$error){
  19            $title = mysql_real_escape_string($title);
  20            $content = mysql_real_escape_string(stripslashes($content));
  21            $sql = “INSERT INTO `posts` (`ID`, `username`, `title`, `content`, `date`) VALUES
  22    (NULL, ”.$_SESSION['userid'].“, ’$title‘, ’$content‘, ”.time().“)”;
  23            mysql_query($sql);
  24            if(mysql_errno()){
  25                $reason .= mysql_error();
  26            }else{
  27                header(“location: blog.php”);
  28            }
  29        }else{
  30            
  31        }
  32        
  33    }
  34    include(“ckeditor/ckeditor.php”);
  35    
  36    // Create class instance.
  37    $CKEditor = new CKEditor();
  38    
  39    // Do not print the code directly to the browser, return it instead
  40    $CKEditor->returnOutput = true;
  41    
  42    // Path to CKEditor directory, ideally instead of relative dir, use an absolute path:
  43    //   $CKEditor->basePath = ’/ckeditor/’
  44    // If not set, CKEditor will try to detect the correct path.
  45    $CKEditor->basePath = ‘ckeditor/’;
  46    
  47    // Set global configuration (will be used by all instances of CKEditor).
  48    $CKEditor->config['width'] = 600;
  49    
  50    // Change default textarea attributes
  51    $CKEditor->textareaAttributes = array(“cols” => 80, “rows” => 10);
  52    
  53    // The initial value to be displayed in the editor.
  54    $initialValue = ‘<p>Put in some content</p>’;
  55    if(strlen($content2) > 0){
  56        $initialValue = $content2;
  57    }
  58    // Create first instance.
  59    $code = $CKEditor->editor(“content”, $initialValue);
  60    echo ‘<?xml version=”1.0″ encoding=”UTF-8″?>’;
  61    ?>
  62    <!DOCTYPE html PUBLIC ”-//W3C//DTD XHTML 1.0 Strict//EN” ”http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd”>
  63    <html xmlns=“http://www.w3.org/1999/xhtml” xml:lang=“en” lang=“en”>
  64    <head>
  65        <title>Blog title</title>
  66        <link href=“main.css” type=“text/css” media=“screen” rel=“stylesheet” />
  67    </head>
  68    <body>
  69        <div class=“maincontent”>
  70            <div class=“top”>
  71                Blog title</div>
  72            <div class=“postform”>
  73                <form method=“POST” action=“?”>
  74                    Title: <input type=“text” name=“title” id=“postformtitle” value=“<?php
  75                    if(isset($title2)){
  76                        echo htmlentities($title2);
  77                    }
  78                    ?>“ /><br />
  79                    Main Content:<br />
  80                    <?php
  81                    echo $code;
  82                    ?><br />
  83                    <input type=“submit” value=“Send!” />
  84                    <input type=“hidden” name=“sub” value=“1″ />
  85                </form>
  86                <div class=“errors”>
  87                    <?php
  88                    if(isset($reason)){
  89                        echo $reason;
  90                    }
  91                    ?>
  92                    </div>
  93            </div>
  94        </div><!– end of maincontent –>
  95    </body>
  96    </html>

As you can see here
  34    include(“ckeditor/ckeditor.php”);
  35    
  36    // Create class instance.
  37    $CKEditor = new CKEditor();
  38    
  39    // Do not print the code directly to the browser, return it instead
  40    $CKEditor->returnOutput = true;
  41    
  42    // Path to CKEditor directory, ideally instead of relative dir, use an absolute path:
  43    //   $CKEditor->basePath = ’/ckeditor/’
  44    // If not set, CKEditor will try to detect the correct path.
  45    $CKEditor->basePath = ‘ckeditor/’;
  46    
  47    // Set global configuration (will be used by all instances of CKEditor).
  48    $CKEditor->config['width'] = 600;
  49    
  50    // Change default textarea attributes
  51    $CKEditor->textareaAttributes = array(“cols” => 80, “rows” => 10);
  52    
  53    // The initial value to be displayed in the editor.
  54    $initialValue = ‘<p>Put in some content</p>’;

I included the file that ckeditor provided me which contained a php class(an object that has several interrelated properties and functions using Object Oriented Programming(I’ll make a tutorial on this later)), and then used the included functions to create the editor html.

I also added a stripslashes function(removes extra backslashes as a result of sending over http headers) to the content variable before it went into the mysql database.

Then comes the second goal: Implement Editing.
Really, all I did was copy the file of put.php, saved it as edit.php and changed a few things, like how variables are first gathered(using sql from post.php), did some preservation tricks, and it al worked. Only change is that when I make a change via edit.php, it moves the changed post to the top because I modified its date. That can be fixed by ordering by post ID, but that is for a later time.
   1    <?php
   2    include(“connect.php”);
   3    $postid = (int)trim($_REQUEST['post']);
   4    if(!isset($_POST['sub'])){
   5        
   6        $sql = “SELECT posts.ID as `ID`,
   7        users.postname as `postname`,
   8        posts.title as `title`,
   9        posts.content as `content`,
  10        posts.date as `date`
  11        
  12        FROM posts 
  13        
  14        INNER JOIN users 
  15        
  16        ON users.ID = posts.username
  17        
  18        WHERE posts.ID = $postid
  19        ORDER BY date DESC”;
  20        $result = mysql_query($sql);
  21        $postdata = array();
  22        while($row=mysql_fetch_array($result)){
  23                $postdata = $row;
  24        }
  25        $title2 = $postdata['title'];
  26        $content2 = $postdata['content'];
  27    }
  28    
  29    
  30    
  31    if(isset($_POST['sub'])){
  32        $title = stripslashes(trim($_POST['title']));
  33        $content = stripslashes(trim($_POST['content']));
  34        $title2 = $title;
  35        $content2 = $content;
  36        $error = false;
  37        $reason = ”;
  38        if(strlen($title) < 3){
  39            $error = true;
  40            $reason .= “Bad Title.\n”;
  41        }
  42        if(strlen($content) < 3){
  43            $error = true;
  44            $reason .= “Bad Post Content.\n”;
  45        }
  46        if(!$error){
  47            $title = mysql_real_escape_string($title);
  48            $content = mysql_real_escape_string(stripslashes($content));
  49            $sql = “UPDATE `posts` SET `title` = ’$title‘,

  50    `content` = ’$content‘, `date` = ”.time().“ WHERE `ID` =”.$postid.“;”;
  51            mysql_query($sql);
  52            if(mysql_errno()){
  53                $reason .= mysql_error();
  54            }else{
  55                header(“location: blog.php”);
  56            }
  57        }else{
  58            

  59        }
  60        

  61    }
  62    include(“ckeditor/ckeditor.php”);
  63    
  64    // Create class instance.
  65    $CKEditor = new CKEditor();
  66    
  67    // Do not print the code directly to the browser, return it instead
  68    $CKEditor->returnOutput = true;
  69    
  70    // Path to CKEditor directory, ideally instead of relative dir, use an absolute path:
  71    //   $CKEditor->basePath = ’/ckeditor/’
  72    // If not set, CKEditor will try to detect the correct path.
  73    $CKEditor->basePath = ‘ckeditor/’;
  74    
  75    // Set global configuration (will be used by all instances of CKEditor).
  76    $CKEditor->config['width'] = 600;
  77    
  78    // Change default textarea attributes
  79    $CKEditor->textareaAttributes = array(“cols” => 80, “rows” => 10);
  80    
  81    // The initial value to be displayed in the editor.
  82    $initialValue = ‘<p>Put in some content</p>’;
  83    if(strlen($content2) > 0){
  84        $initialValue = $content2;
  85    }
  86    // Create first instance.
  87    $code = $CKEditor->editor(“content”, $initialValue);
  88    echo ‘<?xml version=”1.0″ encoding=”UTF-8″?>’;
  89    ?>
  90    <!DOCTYPE html PUBLIC ”-//W3C//DTD XHTML 1.0 Strict//EN” ”http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd”>

  91    <html xmlns=“http://www.w3.org/1999/xhtml” xml:lang=“en” lang=“en”>
  92    <head>
  93        <title>Blog title</title>
  94        <link href=“main.css” type=“text/css” media=“screen” rel=“stylesheet” />
  95    </head>
  96    <body>
  97        <div class=“maincontent”>
  98            <div class=“top”>
  99                Blog title</div>
 100            <div class=“postform”>
 101                <form method=“POST” action=“?”>
 102                    Title: <input type=“text” name=“title” id=“postformtitle” value=“<?php
 103                    if(isset($title2)){
 104                        echo htmlentities($title2);
 105                    }
 106                    ?>“ /><br />
 107                    Main Content:<br />
 108                    <?php
 109                    echo $code;
 110                    ?><br />
 111                    <input type=“submit” value=“Send!” />
 112                    <input type=“hidden” name=“sub” value=“1″ />
 113                    <input type=“hidden” name=“post” value=“<?php echo $postid; ?>“ />
 114                </form>
 115                <div class=“errors”>
 116                    <?php
 117                    if(isset($reason)){
 118                        echo $reason;
 119                    }
 120                    ?>
 121                    </div>
 122            </div>
 123        </div><!– end of maincontent –>
 124    </body>
 125    </html>

Anyway, here’s the sources, the base source zip archive, and again, the ckeditor zip archive.

• Make a page for posting
• Make a form
• Get the SQL for inserting
• Prepare and validate data
• Test page functionality
• Finalize and clean up

Part 1:

Make sure to click on Read More so that you may see Part 2 and the sources.

Part 2:

So, back to the plan, I created the page to post from, and named it “put.php” and modeled the HTML from blog.php. I then put a form for posting in the put.php. At this point, I now have the static page done. By static, I mean that the part of the page that isn’t supposed to change. So, at this point, I need to put in the dynamic part into the page.
Here’s put.php so you may refer to it.
   1    <?php
   2    include(“connect.php”);
   3    if(isset($_POST['sub'])){
   4        $title = stripslashes(trim($_POST['title']));
   5        $content = stripslashes(trim($_POST['content']));
   6        $title2 = $title;
   7        $content2 = $content;
   8        $error = false;
   9        $reason = ”;
  10        if(strlen($title) < 3){
  11            $error = true;
  12            $reason .= “Bad Title.\n”;
  13        }
  14        if(strlen($content) < 3){
  15            $error = true;
  16            $reason .= “Bad Post Content.\n”;
  17        }
  18        if(!$error){
  19            $title = mysql_real_escape_string($title);
  20            $content = mysql_real_escape_string($content);
  21            $sql = “INSERT INTO `posts` (`ID`, `username`, `title`, `content`, `date`) VALUES
  22    (NULL, ”.$_SESSION['userid'].“, ’$title‘, ’$content‘, ”.time().“)”;
  23            mysql_query($sql);
  24            if(mysql_errno()){
  25                $reason .= mysql_error();
  26            }else{
  27                header(“location: blog.php”);
  28            }
  29        }else{
  30            
  31        }
  32        
  33    }
  34    
  35    echo ‘<?xml version=”1.0″ encoding=”UTF-8″?>’;
  36    ?>
  37    <!DOCTYPE html PUBLIC ”-//W3C//DTD XHTML 1.0 Strict//EN” ”http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd”>
  38    <html xmlns=“http://www.w3.org/1999/xhtml” xml:lang=“en” lang=“en”>
  39    <head>
  40        <title>Blog title</title>
  41        <link href=“main.css” type=“text/css” media=“screen” rel=“stylesheet” />
  42    </head>
  43    <body>
  44        <div class=“maincontent”>
  45            <div class=“top”>
  46                Blog title</div>
  47            <div class=“postform”>
  48                <form method=“POST” action=“?”>
  49                    Title: <input type=“text” name=“title” id=“postformtitle” value=“<?php
  50                    if(isset($title2)){
  51                        echo htmlentities($title2);
  52                    }
  53                    ?>“ /><br />
  54                    Main Content:<br />
  55                    <textarea name=“content” id=“postformcontent” cols=“40″ rows=“4″><?php
  56                    if(isset($content2)){
  57                        echo htmlentities($content2);
  58                    }
  59                    ?></textarea><br />
  60                    <input type=“submit” value=“Send!” />
  61                    <input type=“hidden” name=“sub” value=“1″ />
  62                </form>
  63                <div class=“errors”>
  64                    <?php
  65                    if(isset($reason)){
  66                        echo $reason;
  67                    }
  68                    ?>
  69                    </div>
  70            </div>
  71        </div><!– end of maincontent –>
  72    </body>
  73    </html>

As you see, I am using the isset((some form variable here)) thing to see if any data is being submitted. Within the code block (lines 4-32), I prepare the data by using both trim and stripslashes to clean up the content. The most important part is the strip slashes. For if I do not use it, a statement like
Hello “My Dear”
Will end up in the variable as
Hello \”My Dear\”

Obviously, a dirty escape is not what we want to show the user. Handling data like this can be very infuriating if you do not initially handle issues like this.
Furthermore, I duplicate the title and content variables so that the now-unescaped content could be fed back into the form if an error occurred. Then I do further data validation. In my case, I don’t want a post without any content, or a title. Therefore, preventative action is used so I will not end up with an undesired result.
Next, if all my tests are good, then I try to post the content using SQL INSERT. I grabbed the SQL to base it on from a table export, which uses similar syntax, I just needed to modify the example to fit my needs for new dynamic content.

However, when an error has occurred, I need to feed the data back in so the user doesn’t have to type everything back in. Ever had that happen? If you have had that happen because of something like “Oh noes, your session is over!”, I bet you found it really disheartening. Well, don’t make it happen to your users because a database problem happened, or they made a mistake on their side by forgetting a title. Make your systems forgiving!
So, this is why I had those duplicate variables. I can safely put these back into the page by using htmlentities to convert all special characters to their HTML form, as to act as text, and not literal text. Literal text can have other effects, like putting in <a href=”http://evilwebsite.com/with/viruses”>Friendly cute puppies</a> into the post, if it did not have htmlentities, it would allow problematic issues to arise.

Other than that, all I did to any other file, was add a link in blog.php
  59                    <li><a href=“put.php”>Post</a></li>

So, anyway, You may download the Zip Archive that contains the sources so that you may experiment with them.
The Next tutorial will be going over editing, and the next will most likely be going over changing to a visual editor for the post.

Part 1:

Make sure to click on Read more so that you may see Part 2 and the sources(including downloads)!

Part 2:

So first of all, Here is my list of goals

• Create a login page
• Edit the existing blog.php to prove I am logged in
• Create a way to log out
• Add a place for future posting

Additionally, to see how the blog was set up initially, and what has been added to it, please see Tutorial 10 and Tutorial 11.

First, I created a login page, essentially stealing from Tutorial 10 as you will see in the video.
login.php
   1    <?php
   2    include(“connect.php”);
   3    $errortxt = ”;
   4    if(isset($_REQUEST['sub'])){
   5        $username = trim($_REQUEST['username']);
   6        $password = trim($_REQUEST['password']);
   7        //make it safe to see if in the table
   8        $username = mysql_real_escape_string($username);
   9        $password = sha1($password);
  10        //time to query
  11        $sql = “SELECT * FROM `users` WHERE username = ’$username‘ AND password = ’$password‘”;
  12        $result = mysql_query($sql);
  13        $exists = false;
  14        $userid = -1;
  15        while($row = mysql_fetch_array($result)){
  16            $exists = true;
  17            $userid = (int)$row[0];
  18            break;//get out of the while loop
  19        }
  20        if($exists){
  21            $_SESSION['isin'] = 1;
  22            $_SESSION['userid'] = $userid;
  23            header(‘location: blog.php’);
  24        }else{
  25            $errortxt .= “You got something wrong, try again<br />\n”;
  26        }
  27    }
  28    
  29    
  30    
  31    echo ‘<?xml version=”1.0″ encoding=”UTF-8″?>’;
  32    ?>
  33    <!DOCTYPE html PUBLIC ”-//W3C//DTD XHTML 1.0 Strict//EN” ”http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd”>
  34    <html xmlns=“http://www.w3.org/1999/xhtml” xml:lang=“en” lang=“en”>
  35    <head>
  36        <title>Blog title</title>
  37        <link href=“main.css” type=“text/css” media=“screen” rel=“stylesheet” />
  38    </head>
  39    <body>
  40        <div class=“maincontent”>
  41            <div class=“top”>
  42                Blog title</div>
  43            <div class=“login”>
  44                <form action=“?” method=“post”>
  45            Username <input type=“text” name=“username” /><br />
  46            Password <input type=“password” name=“password” /> <br />
  47            <input type=“submit” value=“Log in” />
  48            <input type=“hidden” name=“sub” value=“1″ />    
  49        </form>
  50                <div class=“error”><?php
  51                echo $errortxt;
  52                ?></div>
  53            </div>
  54        </div>
  55    </body>
  56    </html>

Then, I figured, I needed a way to log out. This part is the easiest, as it only includes starting the session essentially, then killing it, and redirecting to the front page.
logout.php
   1    <?php
   2    include(‘connect.php’);
   3    session_destroy();
   4    header(‘location: blog.php’);
   5    ?>

So now what?
Well, now we need to take our login page and our logout page and connect them to the nucleus of our blog, blog.php

You will notice the added content in lines 53-67 in the following
blog.php
   1    <?php
   2    include(“connect.php”);
   3    
   4    echo ‘<?xml version=”1.0″ encoding=”UTF-8″?>’;
   5    ?>
   6    <!DOCTYPE html PUBLIC ”-//W3C//DTD XHTML 1.0 Strict//EN” ”http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd”>
   7    <html xmlns=“http://www.w3.org/1999/xhtml” xml:lang=“en” lang=“en”>
   8    <head>
   9        <title>Blog title</title>
  10        <link href=“main.css” type=“text/css” media=“screen” rel=“stylesheet” />
  11    </head>
  12    <body>
  13        <div class=“maincontent”>
  14            <div class=“top”>
  15                Blog title</div>
  16            <div class=“posts”>
  17                <?php
  18                $sql = “SELECT posts.ID as `ID`,
  19    users.postname as `postname`,
  20    posts.title as `title`,
  21    posts.content as `content`,
  22    posts.date as `date` 
  23    
  24    FROM posts 
  25    
  26    INNER JOIN users 
  27    
  28    ON users.ID = posts.username
  29    
  30    ORDER BY date DESC”;
  31                $result = mysql_query($sql);
  32                while($row=mysql_fetch_array($result)){
  33                ?>
  34                <div class=“post”>
  35                    <span class=“author”><?php
  36                    echo $row['postname'];
  37                    ?></span> Wrote 
  38                    <a class=“title” href=“post.php?post=<?php
  39                    echo htmlentities($row['ID']);
  40                    echo ‘”>’;
  41                    echo htmlentities($row['title']);
  42                    ?></a> at <?php
  43                    echo date(‘l jS \of F Y h:i:s A’,(int)$row['date']);
  44                    ?>
  45                    <div class=“content”><?php
  46                    echo htmlentities($row['content']);
  47                    ?></div>
  48                </div>
  49                <?php
  50                }
  51                ?>
  52            </div><!– end of posts section –>
  53            <div class=“controls”>
  54                <?php
  55                if((int)$_SESSION['isin']){
  56                ?>
  57                Hello, You may
  58                <ul>
  59                    <li><a>Post</a></li>
  60                    <li><a href=“logout.php”>Logout</a></li>
  61                </ul> 
  62                <?php
  63                }else{
  64                    echo ‘You may log in through <a href=”login.php”>this</a>.’;
  65                }
  66                ?>
  67            </div>
  68        </div>
  69    </body>
  70    </html>

In concept, I detected whether logged in or not. If logged in, I would provide appropriate links, if not, I would provide the link to the login page.

The next tutorial will be going over the creation of a post with a What You See Is What You Get editor.

You may download the sources bundled in this Zip Archive for your own use.

Click on Read More to view the sources along with Part 2 and 3 of the video

Part 2:

Part 3:

First of all, I’m going to regurgitate the sources of this project and then explain what everything new means.
File: blog.php

   1    <?php
   2    include(“connect.php”);
   3    
   4    echo ‘<?xml version=”1.0″ encoding=”UTF-8″?>’;
   5    ?>
   6    <!DOCTYPE html PUBLIC ”-//W3C//DTD XHTML 1.0 Strict//EN” ”http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd”>
   7    <html xmlns=“http://www.w3.org/1999/xhtml” xml:lang=“en” lang=“en”>
   8    <head>
   9        <title>Blog title</title>
  10        <link href=“main.css” type=“text/css” media=“screen” rel=“stylesheet” />
  11    </head>
  12    <body>
  13        <div class=“maincontent”>
  14            <div class=“top”>
  15                Blog title</div>
  16            <div class=“posts”>
  17                <?php
  18                $sql = “SELECT posts.ID as `ID`,
  19    users.postname as `postname`,
  20    posts.title as `title`,
  21    posts.content as `content`,
  22    posts.date as `date` 
  23    
  24    FROM posts 
  25    
  26    INNER JOIN users 
  27    
  28    ON users.ID = posts.username
  29    
  30    ORDER BY date DESC”;
  31                $result = mysql_query($sql);
  32                while($row=mysql_fetch_array($result)){
  33                ?>
  34                <div class=“post”>
  35                    <span class=“author”><?php
  36                    echo $row['postname'];
  37                    ?></span> Wrote 
  38                    <a class=“title” href=“post.php?post=<?php
  39                    echo htmlentities($row['ID']);
  40                    echo ‘”>’;
  41                    echo htmlentities($row['title']);
  42                    ?></a> at <?php
  43                    echo date(‘l jS \of F Y h:i:s A’,(int)$row['date']);
  44                    ?>
  45                    <div class=“content”><?php
  46                    echo htmlentities($row['content']);
  47                    ?></div>
  48                </div>
  49                <?php
  50                }
  51                ?>
  52            </div>
  53        </div>
  54    </body>
  55    </html>

File: Post.php

   1    <?php
   2    include(“connect.php”);
   3    $postid = (int)trim($_GET['post']);
   4    $sql = “SELECT posts.ID as `ID`,
   5    users.postname as `postname`,
   6    posts.title as `title`,
   7    posts.content as `content`,
   8    posts.date as `date`
   9    
  10    FROM posts 
  11    
  12    INNER JOIN users 
  13    
  14    ON users.ID = posts.username
  15    
  16    WHERE posts.ID = $postid
  17    ORDER BY date DESC”;
  18    $result = mysql_query($sql);
  19    $postdata = array();
  20    while($row=mysql_fetch_array($result)){
  21            $postdata = $row;
  22    }
  23    
  24    echo ‘<?xml version=”1.0″ encoding=”UTF-8″?>’;
  25    ?>
  26    <!DOCTYPE html PUBLIC ”-//W3C//DTD XHTML 1.0 Strict//EN” ”http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd”>
  27    <html xmlns=“http://www.w3.org/1999/xhtml” xml:lang=“en” lang=“en”>
  28    <head>
  29        <title>Blog title -> <?php
  30        echo htmlentities($postdata['title']);
  31        ?></title>
  32        <link href=“main.css” type=“text/css” media=“screen” rel=“stylesheet” />
  33    </head>
  34    <body>
  35        <div class=“maincontent”>
  36            <div class=“top”>
  37                <a href=“blog.php”>Blog title</a></div>
  38            <div class=“posts”>
  39                <div class=“post”>
  40                    <span class=“author”><?php echo htmlentities($postdata['postname']); ?></span> Wrote 
  41                    <span class=“title”><?php echo htmlentities($postdata['title']); ?></span> at <?php
  42                    echo date(‘l jS \of F Y h:i:s A’,(int)$postdata['date']);
  43                    ?>
  44                    <div class=“content”><?php echo htmlentities($postdata['content']); ?></div>
  45                </div>
  46            </div>
  47        </div>
  48    </body>
  49    </html>

File: Connect.php

   1    <?php
   2    $link = mysql_connect(‘localhost’, ‘phpuser’, ‘phppass’);
   3    if (!$link) {
   4        die(‘Could not connect: ’ . mysql_error());
   5    }
   6    //WE NEED to select the database!
   7    mysql_selectdb(“tutorials_blog”);
   8    ?>

The new INNER JOIN query:
   1    
   2    SELECT posts.ID as `ID`,
   3    users.postname as `postname`,
   4    posts.title as `title`,
   5    posts.content as `content`,
   6    posts.date as `date` 
   7    
   8    FROM posts 
   9    
  10    INNER JOIN users 
  11    
  12    ON users.ID = posts.username
  13    
  14    ORDER BY date DESC

There are major differences between this query and the last one.

• Not selecting *(anything and everything in the tables)
• Use of tableName.field
• Use of the AS term
• Use of INNER JOIN … ON (test of truth)

First of all in this query, we are no longer selecting * (anything and everything), because we have information in the second table that we do not want to bother with. Because of this need for specification, we can consider it adding power to our SQL. We select only what we need, and that includes information from both the user table and the posts table. So, we use the format tableName.fieldName, for a real example, in our “ON” matching case, we use posts.username and users.ID. However, We want to replace the username field in posts with the postname field from the user table. As you can see, this requires some sort of matching and complexity. This is where the INNER JOIN comes in.
We say INNER JOIN and then the table name, in our case users. Then, the most important part, the table data matching. We use ON and then a test of truth, or rather, does Column C from Table A match or satisfy the value in Column A in Table B.
I use ON users.ID = posts.username, however the users.ID and posts.username can be switched. Obviously, this is the most important part because it specifies what we are matching so we get the correct data from both tables.
Please see the video for how I implement this further, as it better show the process of how I compound the process.

Now for the second part, we wanted to put a link from the title of the posts, to a page that has only the post. Now, if you are reading this, you have already used that feature to get to that information. We may in the future implement a “read more” link system. Now, what I do is swap the span tag around the title, with an anchor tag (a). Then I put in a URL, this is where the
  38                    <a class=“title” href=“post.php?post=<?php
  39                    echo htmlentities($row['ID']);
  40                    echo ‘”>’;
  41                    echo htmlentities($row['title']);
  42                    ?></a> at <?php
is implemented.

Then, we simply need to make that post.php.
Simply stated, we needed to use the base.html(included in the source download, and shown in the last tutorial), add the date back in, and prepare the SQL environment and change the SQL just a bit.
The only change in the post page SQL is adding the WHERE clause in the correct place and not being ambiguous with what ID we are referring to. Hence, we end up with “WHERE posts.ID = $postid”
We also need to get the $postid, and as shown above in the blog.php, the link is using the post variable inside of GET(note, I am not referring to the POST variable, the GET is used in the URL). I can safely use this without mysql_real_escape_string or the like because I am casting(forcing the variable type) to a number.
Also, in the process of adding a post.php, I moved the MySQL connect information to connect.php which I am including now in both my blog.php and my post.php.
The rest of the post.php was really just filling in the information into the base template.

This zip Archive contains

• connect.php
• joining.sql(the join query by itself)
• base.html
• blog.php
• main.css
• post.php
• tutorials_blog.sql(the database dump, you can just import this)

Remember, when you try to implement this tutorial on your end, you will need to change the MySQL connect information to work with your server or localhost settings.

Another thing, I forgot to show how to debug your SQL as I first mentioned(sorry), what you can do if you find out that something is not working or selecting the data correctly, after you do the query, you can do
echo mysql_error();
and it will tell you something if something is wrong. If nothing shows up, then it is your logic that is wrong, or you are not using the correct variables with the mysql_fetch_array

Here’s the first video, Part 1:

Please click read more to see the sources, and part 2 and 3.

Part 2:

Part 3:

So, first I start with a base XHTML of my page(look at the bottom for download links, copying the segments below may not function 100%)

   1    <?xml version=“1.0″ encoding=“UTF-8″?>
   2    <!DOCTYPE html PUBLIC ”-//W3C//DTD XHTML 1.0 Strict//EN” ”http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd”>
   3    <html xmlns=“http://www.w3.org/1999/xhtml” xml:lang=“en” lang=“en”>
   4    <head>
   5        <title>Blog title</title>
   6        <link href=“main.css” type=“text/css” media=“screen” rel=“stylesheet” />
   7    </head>
   8    <body>
   9        <div class=“maincontent”>
  10            <div class=“top”>
  11                Blog title</div>
  12            <div class=“posts”>
  13                <div class=“post”>
  14                    <span class=“author”>AUTHOR</span> Wrote 
  15                    <span class=“title”>TITLE</span>
  16                    <div class=“content”>Content</div>
  17                </div>
  18                <div class=“post”>
  19                    <span class=“author”>AUTHOR</span> Wrote 
  20                    <span class=“title”>TITLE2</span>
  21                    <div class=“content”>Content2</div>
  22                </div>
  23            </div>
  24        </div>
  25    </body>
  26    </html>

With the styling CSS file called main.css
   1    .maincontent {
   2        width: 95%;
   3        margin: auto;
   4    }
   5    .top {
   6        font-size: 2em;
   7    }
   8    .author {
   9        font-style: italic;
  10    }
  11    .title {
  12        font-weight: bold;
  13    }
  14    .content:first-letter {
  15    color:#111;
  16    font-size:xx-large;
  17    }
  18    .content:first-line {
  19        font-size: larger;
  20        font-style: oblique;
  21    }
  22    .content {
  23        border-top: dashed thin black;
  24    }
  25    .post {
  26        border-top: dashed thin gray;
  27    }

Along all with all these base elements of style and page, we need a base to set our blog on. This base, naturally in word, will be our database. So I created a database for the blog and put in the following data

   1    
   2    SET SQL_MODE=“NO_AUTO_VALUE_ON_ZERO”;
   3    
   4    –
   5    – Database: `tutorials_blog`
   6    –
   7    
   8    – ——————————————————–
   9    
  10    –
  11    – Table structure for table `posts`
  12    –
  13    
  14    CREATE TABLE IF NOT EXISTS `posts` (
  15      `ID` int(255) NOT NULL AUTO_INCREMENT,
  16      `username` int(255) NOT NULL,
  17      `title` varchar(256) COLLATE utf8_unicode_ci NOT NULL,
  18      `content` longtext COLLATE utf8_unicode_ci NOT NULL,
  19      `date` int(255) NOT NULL,
  20      PRIMARY KEY (`ID`)
  21    ) ENGINE=MyISAM  DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=5 ;
  22    
  23    –
  24    – Dumping data for table `posts`
  25    –
  26    
  27    INSERT INTO `posts` (`ID`, `username`, `title`, `content`, `date`) VALUES
  28    (1, 1, ‘Happy Tacos’, ‘Hello Happy tacos and cheese with nacho and ranch.’, 1277514243),
  29    (3, 1, ‘Some content’, ‘some other content to work with and so on.’, 1277514483),
  30    (4, 1, ‘Jalopies go to town on sundays’, ‘happy go lucky Lorem ipsum dolor sit amet, consectetur adipiscing elit. Phasellus         ac elit ligula. Quisque feugiat vehicula neque, ac elementum diam rutrum nec. Nulla ac cursus purus. Vestibulum dictum dapib        us gravida. Sed laoreet, nisi porta interdum ullamcorper, massa nunc ullamcorper eros, id viverra nunc neque a magna. Duis e        get leo velit. Etiam eget velit neque. Mauris metus odio, bibendum eget auctor non, hendrerit non ipsum. In vehicula magna e        get augue pulvinar aliquam eget eget quam. Nullam in ante vitae velit cursus commodo vel eget risus. Vivamus rhoncus vehicul        a massa, sit amet tincidunt justo tempor non. Maecenas risus odio, porta ut lacinia sit amet, porta in nibh. Etiam interdum,         lectus nec mollis semper, lorem ipsum lacinia massa, ac tincidunt nulla orci vitae magna. Ut molestie tempus placerat. Cras         volutpat, velit nec mattis pellentesque, nisl augue posuere quam, quis fringilla augue nunc sit amet eros. Cum sociis natoq        ue penatibus et magnis dis parturient montes, nascetur ridiculus mus. ’, 1277515071);
  31    
  32    – ——————————————————–
  33    
  34    –
  35    – Table structure for table `users`
  36    –
  37    
  38    CREATE TABLE IF NOT EXISTS `users` (
  39      `ID` int(255) NOT NULL AUTO_INCREMENT,
  40      `username` varchar(32) COLLATE utf8_unicode_ci NOT NULL,
  41      `password` varchar(256) COLLATE utf8_unicode_ci NOT NULL,
  42      `postname` varchar(128) COLLATE utf8_unicode_ci NOT NULL,
  43      PRIMARY KEY (`ID`),
  44      UNIQUE KEY `username` (`username`)
  45    ) ENGINE=MyISAM  DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=2 ;
  46    
  47    –
  48    – Dumping data for table `users`
  49    –
  50    
  51    INSERT INTO `users` (`ID`, `username`, `password`, `postname`) VALUES
  52    (1, ‘kloplop321′, ’5baa61e4c9b93f3f0682250b6cf8331b7ee68fd8′, ‘Kloplop321′);

As you can see, both a table is made not only for posts, but also for users. This is part of the step towards an expandable project, by separating data that can change, and also reduce redundancies in storage.

At this point, since I have the data, all I need to do is

1. Connect to the database
2. Query for posts
3. Query for the usernames of all posts
4. Edit the Template and fill in the data

Essentially, I do that. Here’s the source result. If you watch the video, you will see the process by which I do this, and you will hear me explain everything in detail of how and why.

   1    <?php
   2    $link = mysql_connect(‘localhost’, ‘phpuser’, ‘phppass’);
   3    if (!$link) {
   4        die(‘Could not connect: ’ . mysql_error());
   5    }
   6    //WE NEED to select the database!
   7    mysql_selectdb(“tutorials_blog”);
   8    
   9    echo ‘<?xml version=”1.0″ encoding=”UTF-8″?>’;
  10    ?>
  11    <!DOCTYPE html PUBLIC ”-//W3C//DTD XHTML 1.0 Strict//EN” ”http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd”>
  12    <html xmlns=“http://www.w3.org/1999/xhtml” xml:lang=“en” lang=“en”>
  13    <head>
  14        <title>Blog title</title>
  15        <link href=“main.css” type=“text/css” media=“screen” rel=“stylesheet” />
  16    </head>
  17    <body>
  18        <div class=“maincontent”>
  19            <div class=“top”>
  20                Blog title</div>
  21            <div class=“posts”>
  22                <?php
  23                $sql = “SELECT * FROM `posts` ORDER BY `date` DESC”;
  24                $result = mysql_query($sql);
  25                while($row=mysql_fetch_array($result)){
  26                ?>
  27                <div class=“post”>
  28                    <span class=“author”><?php
  29                    $sql = “SELECT postname FROM users WHERE ID = ”.$row['username'];
  30                    $result2 = mysql_query($sql);
  31                    while($author=mysql_fetch_array($result2)){
  32                        echo $author[0];
  33                    }
  34                    ?></span> Wrote 
  35                    <span class=“title”><?php
  36                    echo $row['title'];
  37                    ?></span> at <?php
  38                    echo date(‘l jS \of F Y h:i:s A’,(int)$row['date']);
  39                    ?>
  40                    <div class=“content”><?php
  41                    echo htmlentities($row['content']);
  42                    ?></div>
  43                </div>
  44                <?php
  45                }
  46                ?>
  47            </div>
  48        </div>
  49    </body>
  50    </html>

As you can see, I took one of the demonstration posts from the base html, and I wrapped it symbolically with each row of data, or posts for the blog. I filled in the blanks for the post information

Download Link

• base.html
• main.css
• blog.php
• tutorials_blog.sql

Are all contained in in this zip archive
Now, the SQL file is only a dump in the database that you can import if you wish to skip the step of manually entering in the information that I did. However, I believe it is best for your experience to follow along with me, rather than just skipping to the end. Programmers learn by doing, not by solely observing the end result(that is called web browsing).

So, here comes the good news:
I have many open days in which I should have time to release maybe even 2 tutorials a day. The problem: I need ideas. I have a couple ideas, but I’m pretty sure I’ll run out quickly.

I have so far ventured into where it comes to creating solutions and not as much into use of certain defined functions anymore. Sort of hard to use only one major function in something I guess!
Which also comes where I am thinking of redoing some of my first tutorials over again(now that I have better experience with the whole process), even if I don’t get any replies, I’ll still redo them. I want a good full series.

Again, sorry for letting you all down for a while there. I have university life coming up in August, so I don’t know how that will turn out, but I hope to fulfill many wishes in the coming time before that.