Exit from a javascript function

Question

I saw many places similar question but couldn't fix it.

Here's my function:

function validate_form(){
     $('#form_data input[type="text"]').each(function(){
            value = $(this).val().trim();
            if(value != '' && value != null && value != 0 ){
                   return true;
            }
     });
     return false;      
}

Its not exiting on return true;. I have also tried e.preventDefault() but no use.

possible duplicate of [How to break/exit from a each() function in JQuery?](http://stackoverflow.com/questions/1799284/how-to-break-exit-from-a-each-function-in-jquery) — JJJ, Apr 01 '13 at 07:57
@DipeshParmar It's the jQuery's `.each()` method. It's not a built-in loop structure so `break` won't work. — JJJ, Apr 01 '13 at 07:58
possible duplicate of [How to Break out of Jquery's Each Loop](http://stackoverflow.com/questions/1784780/how-to-break-out-of-jquerys-each-loop) — Dipesh Parmar, Apr 01 '13 at 07:58
Exactly what should the function do? Is the form considered valid if there's at least one field filled in? Or must all fields be filled in? — Ja͢ck, Apr 01 '13 at 08:05

score 3 · Accepted Answer · answered Apr 01 '13 at 07:59

3

return will return from the function it is in. In your code, that is the anonymous function you pass to each. See the documentation for each:

You can stop the loop from within the callback function by returning false.

You are returning true, not false so you aren't stopping the loop. Change true to false on line 5 of the function.

answered Apr 01 '13 at 07:59

Quentin

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But if you return false, at the end you wouldn't know why the `.each()` ended. – Ja͢ck Apr 01 '13 at 08:00
Set a variable in the scope of `validate_form` and chance it as well as returning false then. – Quentin Apr 01 '13 at 08:02

score 1 · Answer 2 · answered Apr 01 '13 at 08:06

function validate_form(){
     $texts=$('#form_data input[type="text"]'); //cache the object
     var len = $texts.length;
     var validItems=0;
     $texts.each(function(){
            value = $(this).val().trim();
            if(value === ''){ // value of a text input cannot be null
                              // or zero unless you've changed in with JS
                   return false;
            }
            validItems++;
     });
     return len===validItems;      
}

The function doesn't exactly show what item is invalid, just returns false if any of the items is invalid.

score 0 · Answer 3 · answered Apr 01 '13 at 07:57

You have to let the .each() finish before you return from the main function body. You can keep a counter of valid entries you have come across and let the return value depend on that:

function validate_form()
{
    var items = $('#form_data input[type="text"]'),
    count = items.length,
    valid = 0;

    items.each(function() {
        value = $(this).val().trim();
        if (value != '' && value != null && value != 0 ) {
            ++valid;
        }
    });

    return valid !== count;
}

Btw, I've changed the return value to false if there's at least one invalid entry; assuming you're using this as onsubmit="return validate_form()".

Exit from a javascript function

3 Answers3