Numeric Validation using TextBox OnKeyPress event in JavaScript.

<script type = "text/javascript">
        var specialKeys = new Array();
        specialKeys.push(8); //Backspace 
 
        function Check_Is_Numeric(e) 
        {
            var keyCode = e.which ? e.which : e.keyCode;
            var ret = ((keyCode >= 48 && keyCode <= 57) || specialKeys.indexOf(keyCode) != -1);
            document.getElementById("error").style.display = ret ? "none" : "inline";
            return ret;
        }
    </script>
<input type = "text" id = "text1" onkeypress = "return Check_Is_Numeric(event);" ondrop = "return false;" onpaste = "return false;"/>