c# - How to check internet connection is available or not

c# example - check internet connection available or not
check-internet-connection-available-or-not.aspx

<%@ Page Language="C#" AutoEventWireup="true"%>
<%@ Import Namespace="System.Net" %>

<!DOCTYPE html>

<script runat="server">
    protected void Button1_Click(object sender, System.EventArgs e)
    {
        Boolean result = System.Net.NetworkInformation.NetworkInterface.GetIsNetworkAvailable();
        Label1.Text = "internet connection available? " + result.ToString();
    }
</script>

<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
    <title>c# example - check internet connection available or not</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <h2 style="color:DarkBlue; font-style:italic;">
            c# example - check internet connection available or not
        </h2>
        <hr width="550" align="left" color="LightBlue" />  

        <asp:Label 
            ID="Label1" 
            runat="server"
            Font-Size="XX-Large"
            >
        </asp:Label>
        <br /><br />
        <asp:Button 
            ID="Button1" 
            runat="server" 
            Text="Check Internet Connection" 
            OnClick="Button1_Click"
            Height="40"
            Font-Bold="true"
            />
    </div>
    </form>
</body>
</html>