Question

(Scroll down to bottom of post to find solution.)

Got a asp.net page which contains a Datalist. Inside this datalist, there is a template containing a dropdownlist and each time the datalist is filled with an item, a ItemCreatedCommand is called. The itemCreatedCommand is responsible for databinding the dropdownlist.

I think the problem lies here, that I’m using ItemCreatedCommand to populate it – but the strange things is that if I choose the color ‘green’, the page will autopostback, and I will see that the dropdown is still on the color green, but when trying to use it’s SelectedIndex, I always get 0…

protected void DataListProducts_ItemCreatedCommand(object     source, DataListItemEventArgs e)   var itemId = (String)DataListProducts.DataKeys[e.Item.ItemIndex];  var item = itemBLL.GetFullItem(itemId);    var DropDownListColor = (DropDownList)e.Item.FindControl('DropDownListColor');   //Also tried with :  //if(!isPostBack) {   DropDownListColor.DataSource = item.ColorList;  DropDownList.Color.Databind();   // } End !isPostBack)      Label1.test = DropDownListColor.SelectedIndex.toString();  // <- THIS IS ALWAYS 0! *grr*  

I’ve narrowed down the code a bit for viewing, but still you can see what I’m trying to do 🙂 The reason for why I’m doing this, and not declaring the datasource for the colors directly i aspx-page, is that I need to run a test if(showColors), but I do not want to clutter up the html-page with code that I feel should be in the code behind-file.

EDIT: After trying to alter SelectedIndexChange – I’m having a ‘logical’ confusion in my head now – how am I to alter elements inside the datalist? Since, as far as I know – I do not have any way to check which of the items in the datalist this particular dropdownlist belongs to… Or? I’m going to try out a few ways and see what I end up with 😉 But do please post your thoughts on this question 🙂

SOLUTION:

Either bubble the event to ItemCommand, or Handle the event, get the senders parent(which is a datalistItem and manipulate elements in there.

 protected void DropDownListColor_SelectedIndexChanged(object sender, EventArgs e)         {             DropDownList dropDownListColor = (DropDownList)sender;             DataListItem dataListItem = (DataListItem)dropDownListColor.Parent;              var item = items[dataListItem.ItemIndex];             var color = item.ItemColor[dropDownListColor.SelectedIndex];              var LabelPrice = (Label)dataListItem.FindControl('LabelPrice');             LabelPrice.Text = color.Price;          } 

Answer 1

When the DataList is data-bound, the AutoPostBack has not been handled yet, i.e. the values in the ItemCreated event are still the original values.

You need to handle the SelectedIndexChange event of the dropdown control.