How to fire a DropDownList's SelectedIndexChanged() event without full PostBack?
asp.net, drop-down-menu, postback
Solution
You could put the DropDownList into an `<asp:UpdatePanel>` and set the trigger to the `SelectedIndexChanged` event of the DropDownList.
Something like this (don't forget the script manager)
<asp:ScriptManager ID="ScriptManager1" runat="server" />
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:DropDownList ID="drop1" runat="server" OnSelectedIndexChanged="ddlTablo_SelectedIndexChanged" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostbackTrigger ControlID="drop1" EventName="SelectedIndexChanged" />
</Triggers>
</asp:UpdatePanel>
Problem
DropDownList's `SelectedIndexChanged()` Event fills the ListBox on the page. Obviously this posts the page back to the server. Is there any way to make it happen without full postback? ``` protected void ddlTablo_SelectedIndexChanged(object sender, EventArgs e) { List<string> list = new List<string>(); ListBox1.Items.Clear(); var columnNames= from t in typeof(Person).GetProperties() select t.Name; foreach (var item in columnNames) { list.Add(item); } ListBox1.DataSource = list; ListBox.DataBind(); } ```