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how to check for existing element before loading variable

Posted on 2011-03-18
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Last Modified: 2012-05-11
Attached code. This works, but there are circumstances where the "selectprogram" radio button may not exist on the page (or there could be many with that name). In that case, my function fails, I believe because this becomes invalid:

var inputVal = $("#mainform input[name='selectprogram']:checked").val();

If there is no element with the name "selectprogram" then I want to do this:

document.mainform.submit();

This is possible? Do I just need to add another conditional statement? Thank you!
function setprogram(displaycat,task){
	document.mainform.displaycat.value=displaycat;
	document.mainform.task.value=task;

	var inputVal = $("#mainform input[name='selectprogram']:checked").val();

	if (undefined==inputVal){
		if ($('#saveandviewbutton').attr("disabled")==true) {
			$('#workoutalert').fadeIn();
		}
	} else {
		document.mainform.submit();
	}
}

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Question by:bbdesign
2 Comments
 
LVL 83

Accepted Solution

by:
leakim971 earned 2000 total points
ID: 35168933
$("#mainform input[name='selectprogram']:checked").length return the number of object found.

var $selection = $("#mainform input[name='selectprogram']:checked");
if( $select.length == 1) {
// only one found, phew !!!
}
else if( $select.length >=1 ) {
// more than one found !!!!
}
else {
// ok submit !!
 document.mainform.submit();
}

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Author Comment

by:bbdesign
ID: 35183777
.length -- great! Easy, too. Thanks.
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