IE8 and JQuery's trim()

I am making use of trim() like so:

if($('#group_field').val().trim()!=''){

Where group_field is an input element of type text. This works in Firefox but when I try it on IE8 it gives me this error:

Message: Object doesn't support this property or method

When I remove the trim(), it works fine on IE8. I thought the way I am using trim() is correct?

Thanks all for any help

Try this instead:

if($.trim($('#group_field').val()) != ''){

More Info:

• http://api.jquery.com/jQuery.trim/

You should use $.trim, like this:

if($.trim($('#group_field').val()) !='') {
    // ...
}

As far as I know, Javascript String does not have the method trim. If you want to use function trim, then use

<script>
    $.trim(string);
</script>

Another option will be to define the method directly on String in case it's missing:

if(typeof String.prototype.trim !== 'function') {
  String.prototype.trim = function() {
    //Your implementation here. Might be worth looking at perf comparison at
    //http://blog.stevenlevithan.com/archives/faster-trim-javascript
    //
    //The most common one is perhaps this:
    return this.replace(/^\s+|\s+$/g, ''); 
  }
}

Then trim will work regardless of the browser:

var result = "   trim me  ".trim();

To globally trim input with type text using jQuery:

/**
 * Trim the site input[type=text] fields globally by removing any whitespace from the
 * beginning and end of a string on input .blur()
 */
$('input[type=text]').blur(function(){
    $(this).val($.trim($(this).val()));
});