Activing Input type="image" with "e

[Anon]

I have the following code to submit a form:

<input type="image" src="submit.png" name="submit" value="submit">

I then need to check the value of $submit. This is simple enough if the user clicks on the graphic, $submit_x and $submit_y are set to to coordinate values. But if the user hits the enter key to submit, rather than point and click on the graphic, I can't tell if the user submitted the form or just navigated to the web page manually.

Is there any way to tell if the form was submitted through the user pressing enter rather than clicking the graphic?

[[deleted]]

Have you tried adding a hidden input item with some default value and checkin for that 'instead' of the submit image?

[Anon]

can't you just check for it with something like

if submit != ""{
//...
}else{
//...
}

In other words just checking to see if submit has a value other than null? Indicating the form has been submitted or am I barking up the wrong tree?