Validate field using Javascript

<script type="text/javascript">
<!-- hide


function validateFormLocal(theForm) {

   // check for a post title
   if (theForm.frmTitle.value == "") {
        alert("Please enter a title for the post.");
        theForm.frmTitle.focus();
        return false;
    }

   // if all checks pass submit form
   return true;
}

// done hiding -->
</script>


<form action="process.php" method="post" onsubmit="return validateFormLocal(this)" name="FormPost">

   <label for="frmTitle" class="txtlabel">Title:</label>
   <span><input type="text" name="frmTitle" id="frmTitle"></span>

</form>