<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="ControlsExample3.aspx.cs" Inherits="FormControls.ControlsExample3" %>

 

<!DOCTYPE html>

 

<html xmlns="http://www.w3.org/1999/xhtml">

<head id="Head1" runat="server">

    <title>WFC Example: Client-Side Intercept</title>

    <script lang="javascript" type="text/javascript">

        function Validate() {

            var amount = document.getElementById("txtAmount").value;

 

            if (isNaN(amount)) {

                alert("You must enter a number");

                return false;

            }

            else if (amount < 100) {

                document.getElementById("lblDisplay").innerHTML = "From the Client: The amount must be 100 or more."

                return false;

            }

            else if (amount >= 100) {

                document.getElementById("lblDisplay").innerHTML = "From the Client: The amount must OK."

                alert("That amount is OK.");

                return true;

            }

        }

    </script>

 

</head>

<body>

    <h3>Method 1: Intercepting a Web Form (ASPX) Control on the client-side <br />

        The client-side script can also stop the form submission.</h3>

 

    <form id="form1" runat="server">

       

    <asp:Label ID="Label1" runat="server" ForeColor="#000099"

        Text="Enter an amount:"></asp:Label>

    <br />

    <asp:TextBox ID="txtAmount" runat="server"></asp:TextBox>

    <br />

    <br />

    <asp:Button ID="btnSubmit" Text="Submit" OnClientClick="return Validate();" runat="server" Width="77px" OnClick="btnSubmit_Click" />

    <br />

    <asp:Label ID="lblDisplay" runat="server" ForeColor="#CC3300"></asp:Label>

    </form>

</body>

</html>