That's done something using "$_GET" to create check against a variable...
In php, you have assign variables to the end of the url and then call them back using the global variable $_GET, so to create an easy include function, you would have your links changing that variable, and a block of code to check what that variable is, so for example, if we had the variable "page" and the includes 1.php and 2.php and the variables for those pages being "one" and "two" respectively, we would have the big block of code to check what the variable is:
php code:
$page = (isset($_GET['page'])) ? $_GET['page'] : "";
if($page=="" or $page=="one"){
include("1.php");
}
elseif($page=="two"){
include("2.php");
}
This uses the $_GET and sets the variable $page to the value that has been set in the URL (for example www.bbq.com
?page=one would mean the variable page is set to one), then checks what the variable is, and if the variable is one
or not set then it includes 1.php and if the variable is two it includes 2.php.
To change this variable (ie, when you click a link) you use the following code:
php code:
<a href="?page=two">goto page 2</a>
This is a self-explanatory line of code.
This method can also be used to string variables and can be incredibly useful. To string variables, you just set the variables in the same way. If you need any more help feel free to post
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