Jquery CheckBox

Question

var $field = $(this);
            if ($field.is('input')) {
                alert(1);
                if ($field.attr('type') == 'checkbox') {
                    alert(2);
                    if ($field.attr('value') == "true")
                        return $field.attr('checked');
                }

                return $field.val();
            }

I want to check if value of checkbox is true i add attribute checked = checked for checkbox. but my code is wrong. please help me.thanks

Answer 1

Change the condition to

$("input:checkbox").val() == "true"

and for checking the checkbox you can use

$("input:checkbox").attr ( "checked" , true );

You can select a checkbox using

$("input:checkbox")

and value using

$("input:checkbox").val()

If you want to check all the checkboxes with attribute value true then you can use

$(document).ready ( function ()
     {
      var checkBoxes = $("input:checkbox");   
      checkBoxes.each ( function () {
          if ( $(this).val() == "true" )
          {
           $(this).attr ( "checked" , true );
          }
      });
     });

Answer 2

You can use the :checked selector to greatly help with this.

var $field = $(this);
return $field.is(':checked');

This will return a proper bool. If you return the attr('checked') or the val(), you'll end up with a string, which is probably not what you want.

See http://docs.jquery.com/Selectors/checked

Answer 3

I'm try use Phoenix way but it's still wrong.
Code Line:

if ( $(this).val() == "true" )
  {
     $(this).attr ( "checked" , true );
  }

can't run. I used to alert() to check wrong but it not run.

Please help me
best regards,
Vicky

Answer 4

.attr("checked") will return true for checked and false for unchecked