Validate ASP.Net TextBox length based on Label value using jQuery and JavaScript

Hi nauna,

Refer below sample.

HTML

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<script type="text/javascript">
    $(function () {
        var message = "Welcome To ASPForums.net";
        $("#lblMessage").html(message.length);
        $("#btnSubmit").click(function () {
            var txtValue = $("#txtMessage").val();
            var lblValue = $("#lblMessage").html();
            if (lblValue >= txtValue.length) {
                alert("textbox value should be greater than label value");
            }
            return false;
        });
    });
</script>
<div>
    Message :
    <asp:TextBox runat="server" ID="txtMessage" TextMode="MultiLine" />
    <br />
    <asp:Label ID="lblMessage" runat="server" />
    <asp:Button Text="Submit" runat="server" ID="btnSubmit" />
</div>

Screenshot