Problem in FormView

NOclipus · February 7th, 2009, 09:05 PM

Greetings. I have FormView with Insert as default mode, and inside InsertItemTemplate, I have a DropDownList. Now, problem: I created Page_Load event, and at this event, I want to populate DropDownList with data from DB by using SqlReader (the page is used to add articles, and category where new article belongs is chosen from DropDownList.) But when I try to use DropDownList1.DataSource I get "name DropDownList1 doesn't exist in current context" error. I've spent three hours tying to solve it, and I'm really desperate. Any ideas, please?

Lee Dumond · February 8th, 2009, 12:51 AM

As your DropDownList is nested, you need to use the FindControl method and cast the found control to a DropDownList.

NOclipus · February 8th, 2009, 01:21 PM

Yes, that seems to do the trick. Hovewer, I have one more question: How do I bind data to dropdownlist? I've tried

Code:

<asp:DropDownList ID="ddlCategory" runat="server" SelectedValue='<%# Bind("categoryId") %>'></asp:DropDownList>

which doesn't seem to work, as it says that "Databinding methods such as Eval(), XPath(), and Bind() can only be used in the context of a databound control.".
The code used to populate dropdownlist:

Code:

DropDownList ddl;

ddl = (DropDownList)FormView1.FindControl("ddlCategory");

ddl.DataSource = dReader;
ddl.DataTextField = "name";
ddl.DataValueField = "numberId";
ddl.DataBind();

Sorry to still bother, but any ideas?

EDIT:

Code:

SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["dbConn"].ToString());
conn.Open();
string sSql = "SELECT numberId, name FROM Categories ORDER BY numberId DESC";
SqlCommand cmd = new SqlCommand(sSql, conn);
SqlDataReader dReader;
dReader = cmd.ExecuteReader();

This is dReader. All pasted coded is used at FormView1_DataBound event.

EDIT:

Oh well, I solved the problem by deleting all methods and adding data to dropdownlist by ObjectDataSource. You can lock this thread.

Lee Dumond · February 8th, 2009, 01:44 PM

Right. As you have discovered, if you don't using a page-level datasource, your data-binding expressions won't work. This is because the page attempts to evaluate the data-binding expression before the control is actually bound to any data.