php, how to catch if a variable is never sent (post or get)

[rickyj]

Hi,

 

I'm running into something that seems quite trivial. I'm primarily a java programmer, but am creating a web site that has a bit of php code.

 

The problem is, I have created a search page in php that querries a db, and returns to self with the results.

 

One of the problems im having is that if a user goes directly to search php, then there is an error thrown because there is no variable sent to this page.

 

I need a way of "catching" this error without having to define.

 

I have tried something like:

 

php:

 

if(  $_POST['myVar'] == NULL ){

$variableDefinedfromMyVar = "no search submited";

}

 

 

// problem is "$_POST['myVar']" thows an error since myVar is undefined

 

I also need to catch other nonsubmitted variables but cant see how ???? any suggestions

[hitman6003]

Try the isset, empty, and is_null functions...

 

http://www.php.net/isset

http://www.php.net/empty

http://www.php.net/is_null