How to set DropDownList's selected value inside a Repeater?

Question

I need to create a group of DropDownLists to show and allow change of a property group for an item.

I have the following code on my ASP page.

<asp:Repeater runat="server" ID="repeaterProperties">
    <ItemTemplate>
        <p><asp:DropDownList runat="server" ID="ddProperty" OnInit="ddProperty_OnInit" /><p>
    </ItemTemplate>
</asp:Repeater>

The ddProperty_OnInit populates the DropDownList with all the possible values with a database query.

How can I set the selected value of each created DropDownList according to the Repeater's source data?

Let's say, for example, that we have the possible property values of A, B and C.
If the database output for the Repeater contains two of those values, A and B, the Repeater outputs two DropDownLists, both with all 3 values availabla and the first one with A as selected value and the second one with B as selected value.

Edit:
It seems that adding OnItemDataBound="repeater_ItemDataBound" to the Repeater and selecting the appropriate value in there is not the way to go in my case. This is because I also need to save the possibly changed values to a database.

The ItemDataBound event of the Repeater is fired before the OnClick event on a Button and changes the selected values to their old values before the new selections can be saved.

Any suggestion on how to work around this?

Current code:

<asp:Repeater runat="server" ID="repeaterJako" OnItemDataBound="repeater_ItemDataBound">
<ItemTemplate>
    <asp:DropDownList id="ddJako" runat="server" OnInit="ddJako_OnInit">
    </asp:DropDownList><br />
</ItemTemplate>
</asp:Repeater>
<asp:Button runat="server" id="updateButton" Text="Save" OnClick="update_OnClick" />

In the code-behind, ddJako_OnInit populates the drop down list with all the possible choises, while the repeater_ItemDataBound uses the method suggested by Bryan Parker to select the proper value.

Solution 1

Maybe I'm misunderstanding something about your question... but it seems like this is exactly what OnItemDataBound is for. :)

Use FindControl to get a reference to your DropDownList in the event handler. Also check to make sure the item is not the header/footer. The example from MSDN does both these things:

http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.repeater.onitemdatabound.aspx

Solution 2

In regard the problem I specified in my edit, the time of the DataBind plays an important role. I used to do the databinding in the Page_Init event, which caused the repeater_ItemDataBound event to be fired before the button_OnClick event.

The solution was to move the databinding to the Page_PreRender event.
The population of the DropDownList with all the choises is still done in its OnInit event.

Comments

[vipirtti]

@jwalkerjr I did, untill I found out that it did not help my situation. Well, I did figure it out just a minute ago, so might as well. It's a good answer and mine will only add to it.