DropDownList's SelectedIndexChanged event not firing

Question

I have a DropDownList object in my web page. When I click on it and select a different value, nothing happens, even though I have a function wired up to the SelectedIn

Answer 1

Also make sure the page is valid. You can check this in the browsers developer tools (F12)

In the Console tab select the correct Target/Frame and check for the [Page_IsValid] property

If the page is not valid the form will not submit and therefore not fire the event.

Answer 2

Set DropDownList AutoPostBack property to true.

Eg:

<asp:DropDownList ID="logList" runat="server" AutoPostBack="True" 
        onselectedindexchanged="itemSelected">
    </asp:DropDownList>

Answer 3

try setting AutoPostBack="True" on the DropDownList.

Answer 4

Instead of what you have written, you can write it directly in the SelectedIndexChanged event of the dropdownlist control, e.g.

protected void ddlleavetype_SelectedIndexChanged(object sender, EventArgs e)
{
 //code goes here
}

Answer 5

Add property ViewStateMode="Enabled" and EnableViewState="true" And AutoPostBack="true" in drop DropDownList

Answer 6

For me answer was aspx page attribute, i added Async="true" to page attributes and this solved my problem.

<%@ Page Language="C#" MasterPageFile="~/MasterPage/Reports.Master"..... 
    AutoEventWireup="true" Async="true" %>

This is the structure of my update panel

<div>
  <asp:UpdatePanel ID="updt" runat="server">
    <ContentTemplate>

      <asp:DropDownList ID="id" runat="server" AutoPostBack="true"        onselectedindexchanged="your server side function" />

   </ContentTemplate>
  </asp:UpdatePanel>
</div>