The $_POST Function

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

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://www.w3schools.com/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.