How do you call functions on an 'html submit' within same page?

[soma56]

I know how to redirect users using a simple form as a means of running a php script:

 

<form action="mynewpage.php" method="post">
Name: <input type="text" name="name" value="" />
    <br />
    <input type="submit" name="submit" value="Name" />
    </form>

 

However, what if I wanted to include everything on the same page? I know that the form action should be as follows:

 

<form action="" method="post">

 

Would I do a php include for the functions? If so, what's the best way (or any way for that matter) to call them when the user clicks the submit button?

[Pikachu2000]

<?php
if(isset($_POST['submit'] {
     // Do this stuff if the form has been submitted . . . can be functions, includes(), etc.
} else {
     // DO this other stuff if it hasn't been submitted . . .
}
?>
<form action="" method="POST">
. . .  form stuff here . . .
</form>