Jquery RegEx Validation


I am wanting to check if an input field has the attribute "pattern" and if so, preform a regex check aganst said pattern.I know this is already done by HTML5, but I am wanting to handle the event myself. I am receiving this error: Uncaught TypeError: Object a-zA-Z has no method 'test'

 ///Check Perform Reg///////////////////////////////////////////////////////
         if ($(this).attr("pattern")) {
             var reg = $(this).attr("pattern");
             var currentValue = $(this).val();

             if (reg.test(currentValue)) {
                 $(this).after($error.clone().text("Invalid Input.Try Again."));
                 hasError = true;
                 return false;


Still no luck,

also here is my html:

    <input class="formInput" name="First Name" pattern="^[A-Za-z_-][A-Za-z0-9_-]*$" type="text"  id="frmFirst" min="2" maxlength="30"  required="required"/>
    <span>First Name</span>

Best Solution

Normally regular expression with javascript / jquery handle like

var reg = /pattern/;
if (reg.test($(this).val())) {
    // perform some task