isset($_POST['message']) vs $_POST['message']!=''

[Q695]

How are these not saying to check for the same thing, because when I run the isset it's thinking $_POST['message']! that a blank entry is something there, but !='' is saying that a blank entry isn't there?  I tried the isset a few times, but every time it came out allowing a blank message the same way.

 

Is that a bug with WAMP:Apache Version :2.2.17/PHP Version :5.3.4?

[akphidelt2007]

No, it's per the documentation. Isset simply checks to see if the key/variable exists regardless of the value. You can use...

if(isset($_POST['message']) && !$_POST['message'])

This would indicate the key/variable exists but the value is empty, blank, 0, false, etc...

Edited May 7, 2013 by akphidelt2007

[Q695]

But the way $message is setup it would by default be set to NULL, and therefore not set.

[mac_gyver]

all text and textarea form fields are set any time the form is submitted, even if they are empty. only checkbox/radiobuttons will not be set when they are not selected.

 

what makes you think your variable from a form will/should be a null?

 

your form processing code should test if a form has been submitted, then all the code within the form processing code doesn't need to individually test if text/textarea fields are set. they will be.

[Q695]

You can send a blank chat message by accident.

[mac_gyver]

a user or a hacker could send your script anything that can be imagined.