Validating an Optional field with Bootstrap Jquey

[virtualweb]

Hi:

My form asks the user the following question:

If you have a "Discount Code" enter it below.

Most people will not have a code so the field cannot be required, but when it is filled, I want the jquery validation to guard me against malicious code.

The form works great. The field is checking for "alpha numeric values" and "minimum characters" but I cannot submit it unless the field is filled out.

I want the form to validate if and when the field is filled out only.

THIS IS THE HTML:

<div class="form-group">
<div class="form-group">
	<label class="col-sm-3 control-label">Enter Code<span class="asterisk">*</span></label>
	<div class="col-sm-7">
	<input type="text" name="Discount_Code" class="form-control popovers"  placeholder="Enter Code">
	</div>
</div><!-- /.form-group -->

THIS IS THE JAVASCRIPT: (jquery)

   <script type="text/javascript">



var BlankonFormValidation = function () {

    return {

        // ====================
        // CONSTRUCTOR APP
        // ====================
        init: function () {
            BlankonFormValidation.jqueryValidation();
        },

        // ====================
        // JQUERY VALIDATION
        // ====================
        jqueryValidation: function () {
        	
        	
        	// START TEXTATERA VALIDATION //
        	
        	
            if($('#sample-validation-2').length){

              $('#sample-validation-2').validate({
                    rules:{
                      
                            Discount_Code:{
                            nosplchars:true,
                            minlength: 5
                            }
                    },
                    messages: {
                       
                        Discount_Code: {
	    nosplchars: "no special characters",
	    minlength: jQuery.validator.format("Enter at least {0} characters")
	    }
                    },
                    highlight:function(element) {
                        $(element).parents('.form-group').addClass('has-error has-feedback');
                    },
                    unhighlight: function(element) {
                        $(element).parents('.form-group').removeClass('has-error');
                    }
                   
                });
            }

			

        
            // START SPECIAL CHARS REGEX
            
	$.validator.addMethod("nosplchars", function(value, element) {          
				return /^[a-zA-z0-9\s]+$/.test(value);
			}, "Special characters are not allowed");
	
              // END SPECIAL CHARS REGEX	


          
        }

    };

}();

// END TEXTATERA VALIDATION //

// Call main app init
BlankonFormValidation.init();


       
    </script>

Thanx beforehand
VirtualWeb