Determining presence of a variable

[lalit.nagalkar]

HI all

 

I am new to PHP

I want to create a simple login script.

 

I want to know a workaround to know if a variable is present or not, e.g. a hidden field ($_POST["myHiddenField"]).

 

Is there anyway in PHP to determine if this is users first request? So that when user posts wrong info the same script will be executed with the difference that user sees an error message. On success a success page will be shown.

 

The first time user sees the form there will not be any post data from user side hence user will see only user id, password and a submit button. I am using a hidden field to determine if user has posted the data.

 

 

Thank you all.

 

[Alex]

isset

 

Example:

 

if(isset($_POST['myHiddenField']))
{
     // ...
}

[oni-kun]

Use a really simple function called isset such as.. here:

if (!isset($_POST['username']) //If it isn't set
{
  echo "Error. Please enter a username";
} else { 
  echo "Welcome $_POST['user'] !";
}