PHP $_POST Function

PHP $_POST Function 

The built-in $_POST function is used to collect values in a form with method="post". 

The $_POST Function 

The built-in $_POST function is used to collect values from a form sent with method="post". 

Information sent from a form with the POST method is invisible to others and has no limits on the amount of information to send. 

Note: However, there is an 8 Mb max size for the POST method, by default (can be changed by setting the post_max_size in the php.ini file). 

Example 

<form action="welcome.php" method="post">

 Name: <input type="text" name="fname" />

 Age: <input type="text" name="age" />

 <input type="submit" />

</form>  

When the user clicks the "Submit" button, the URL will look like this: 

http://siteurl/welcome.php  

The "welcome.php" file can now use the $_POST function to collect form data (the names of the form fields will automatically be the keys in the $_POST array): 

Welcome <?php echo $_POST["fname"]; ?>!<br />

You are <?php echo $_POST["age"]; ?> years old. 

 

When to use method="post"? 

Information sent from a form with the POST method is invisible to others and has no limits on the amount of information to send.However, because the variables are not displayed in the URL, it is not possible to bookmark the page. 

The PHP $_REQUEST Function 

The PHP built-in $_REQUEST function contains the contents of both $_GET, $_POST, and $_COOKIE. 

The $_REQUEST function can be used to collect form data sent with both the GET and POST methods. 

Example 

Welcome <?php echo $_REQUEST["fname"]; ?>!<br />

You are <?php echo $_REQUEST["age"]; ?> years old.