Sir,
I have used Update Panel control, but seems like page is still refreshing.....
Below is the HTML code i am using:
<body>
<form id="form1" runat="server">
<div>
<span style ="font-family:Arial">
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
Select Continent :<asp:DropDownList ID="ddlContinents" runat="server" AutoPostBack = "true" OnSelectedIndexChanged="ddlContinents_SelectedIndexChanged">
<asp:ListItem Text = "--Select Continent--" Value = ""></asp:ListItem>
</asp:DropDownList>
<br />
<br />
Select Country :<asp:DropDownList ID="ddlCountry" runat="server" Enabled = "false" AutoPostBack = "true" OnSelectedIndexChanged="ddlCountry_SelectedIndexChanged">
<asp:ListItem Text = "--Select Country--" Value = ""></asp:ListItem>
</asp:DropDownList><br />
<br />
Select City :<br />
<asp:DropDownList ID="ddlCity" runat="server" Enabled = "false" AutoPostBack = "true" OnSelectedIndexChanged="ddlCity_SelectedIndexChanged">
<asp:ListItem Text = "--Select City--" Value = ""></asp:ListItem>
</asp:DropDownList><br />
<asp:Label ID="lblResults" runat="server" Text="" Font-Names = "Arial"></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
<br />
</span>
<br /><br />
<span style ="font-family:Arial"> </span>
<br /><br />
<span style ="font-family:Arial"> </span>
<br /><br />
</div>
</form>
</body>
========================================================
as per the article .vb code is working fine ........... But after using Update Panel control the page is still refreshing..