How to check for an empty input value

Question

Possible Duplicate:
Check if textbox has empty value

How do I check if an input value is blank?

I am currently doing:

if($(#inputid).val()=="") {
    alert("its blank");
}

Don't you have an error here? It should be $('#inputid').val()) — Anthony, Feb 24 '12 at 10:55
Keep the JavaScript error console open while you're testing. The error messages are shown there. — JJJ, Feb 24 '12 at 10:56

score 4 · Answer 1 · answered Feb 24 '12 at 10:55

4

Try quoting your selector string:

if ($("#inputid").val() == "") {
    ...

You might want to trim to stop whitespace from counting:

if ($.trim($("#inputid").val()) == "") {
    ...

answered Feb 24 '12 at 10:55

karim79

score 2 · Answer 2 · answered Feb 24 '12 at 10:56

2

Try:

if( !$.trim($("#inputid").val()).length ) {
  alert("blank");
}

answered Feb 24 '12 at 10:56

Naveed

I am not sure whether this is what you have wanted to write :). – kapa Feb 24 '12 at 11:00
Yes. You are right. Is it OK now? :) – Naveed Feb 24 '12 at 11:02

elclanrs · Answer 3 · 2012-02-24T11:11:05.800

1

You can just do:

if (!$('#id').val()) { 
    //is blank 
}

edited Feb 24 '12 at 11:11

answered Feb 24 '12 at 10:57

elclanrs

1

Actually, you've got your logic wrong. That if-clause will only execute if the value is NOT blank. – PatrikAkerstrand Feb 24 '12 at 10:58

3 Answers3