jQuery Validation plugin: validate check box

Question

I am using jQuery Validation plugin to validate check box since it does not have default option, One should be selected and max two check boxes can be selected, these is the criteria. I am not getting any error and it is not validating. I am extending it like below,

  <input type="checkbox" name="test[]" />x
   <input type="checkbox" name="test[]"  />y
   <input type="checkbox" name="test[]" />z
     $("#formid").validate({
  rules: {
    test[]: { 

            required: function(elem)
            {
                return $("input.select:checked").length > 0;
            }

          },
messages: { 

    test[]: "You must check at least 1 box"
  }
 });

Answer 1

You had several issues with your code.

1) Missing a closing brace, }, within your rules.

2) In this case, there is no reason to use a function for the required rule. By default, the plugin can handle checkbox and radio inputs just fine, so using true is enough. However, this will simply do the same logic as in your original function and verify that at least one is checked.

3) If you also want only a maximum of two to be checked, then you'll need to apply the maxlength rule.

4) The messages option was missing the rule specification. It will work, but the one custom message would apply to all rules on the same field.

5) If a name attribute contains brackets, you must enclose it within quotes.

DEMO: http://jsfiddle.net/K6Wvk/

$(document).ready(function () {

    $('#formid').validate({ // initialize the plugin
        rules: {
            'test[]': {
                required: true,
                maxlength: 2
            }
        },
        messages: {
            'test[]': {
                required: "You must check at least 1 box",
                maxlength: "Check no more than {0} boxes"
            }
        }
    });

});