ASP.Net下拉列表没有返回selectedindexchanged事件的索引

Question

I have a dropdownlist control with a selectedindexchanged event that fires correctly . However, when you select an item from the list the index value that is returned to the selectedindexchanged event does not change; the list box pops back tot he first item in the list. Any help would be appreciated. ~susan~

ASP DROP DOWN LIST CONTROL :

 <asp:DropDownList ID="CuisineList" runat="server" Width="100" 
    AutoPostBack = "true" onselectedindexchanged="CuisineList_SelectedIndexChanged" >
 </asp:DropDownList>

DATA BOUND TO CONTROL IN PAGELOAD EVENT:

 protected void Page_Load(object sender, EventArgs e)
 {
    //Load drop down lists for restaurant selection

    BLgetMasterData obj = new BLgetMasterData();

    var cusineList = obj.getCuisines();
    CuisineList.DataSource = cusineList;
    CuisineList.DataBind();
    CuisineList.Items.Insert(0, "Any");

SELECTEDINDEXCHANGEDEVENT:

   protected void CuisineList_SelectedIndexChanged(object sender, EventArgs e)
    {

        if (IsPostBack)
        {
            string def = this.CuisineList.SelectedItem.Value;
            //aLWAYS returns index '0'
        }
    }

Answer 1

You need to put your Dropdownlist binding code under !IsPostBack() in the page_load event. like...

protected void Page_Load(object sender, EventArgs e) { 
 if(!IsPostBack)
 {
  BLgetMasterData obj = new BLgetMasterData();

  var cusineList = obj.getCuisines();
  CuisineList.DataSource = cusineList;
  CuisineList.DataBind();
  CuisineList.Items.Insert(0, "Any");
 }
}

Reason: Whenever your SelectedIndex Change Event fires, the Page_load event is called before the SelectedIndex Change event and your dropdown data rebinded , that's why your currect selection was lost .