我将如何从ondatabinding事件中获取数据注释记号

Question

我有一个网格视图，需要从ASP.NET/C#中的事件ondatabinding访问该行的datakeyname。我如何从ondatabindings访问数据键？这甚至可以由三个不同网格视图中的一个调用。我该如何从ondatabinding中获取这些行的datakeyname？

ondatabinding="PreventErrorOnbinding"

 DataKeyNames="ID"
 <asp:TemplateField HeaderText="Purpose" SortExpression="Purpose" ItemStyle-Width="50px" HeaderStyle-Width="50px" HeaderStyle-Wrap="false">
                        <ItemTemplate>
                            <asp:Label ID="LabelPurpose" runat="server" Text='<%# Eval("Purpose") %>'></asp:Label>
                        </ItemTemplate>
                        <EditItemTemplate>
                            <asp:DropDownList ID="ddPurpose1" ondatabinding="PreventErrorOnbinding" class="txtSize" SelectedValue='<%# Bind("Purpose") %>' AppendDataBoundItems="true" runat="server">
                            </asp:DropDownList>
                            <asp:RequiredFieldValidator ID="ddPurposeRequiredFieldValidator1" runat="server" Display="Dynamic" ForeColor="Red"
                            ErrorMessage="Select a purpose type." InitialValue="" ControlToValidate="ddPurpose1" ValidationGroup="relationshipGroup2" />                            
                        </EditItemTemplate>

C#：

protected void PreventErrorOnbinding(object sender, EventArgs e)
{
    DropDownList ddl = (DropDownList)sender;
    ddl.DataBinding -= new EventHandler(PreventErrorOnbinding);
    ddl.AppendDataBoundItems = true;
    ListItem li = new ListItem("Select a purpose type.", "");
    ddl.Items.Insert(0, li);
    //Get this purpose from the db and insert it into the list and then add the other default items also. 
    //This will allow us to edit items that do not exist within the list that were set before this was a dropdown list when it was a textbox.
    try
    {
        ddl.DataBind();
    }
    catch (ArgumentOutOfRangeException)
    {
        GridViewRow row = (GridViewRow)ddl.NamingContainer;
        //int index = GetColumnIndexByName(row, "ID");
        //Int64 columnValue = Convert.ToInt64(row.Cells[index].Text.Trim());
        //similar to this but the gridview would need to be accessed dynamically.
        // var id = gvTransactionHistory.DataKeys[rowIndex].Values["ID"];
        int RowIndex = row.RowIndex;
        //Int64 rowID = Convert.ToInt64(????.DataKeys[RowIndex].Values["ID"].ToString().Trim());
        //ddl.SelectedValue = Globals.GetDropDownValue(rowID);
        //get item from the db for this contact
        //append the rest
        ddl.Items.Clear();
        ddl.DataSourceID = ddPurposeSqlDataSource.ID;
        ddl.DataBind();
    }
}

Answer 1

明白了！

        GridViewRow row = (GridViewRow)ddl.NamingContainer;
        DataRow dr = ((DataRowView)row.DataItem).Row;
        string id = dr["ID"].ToString().Trim();
        string id2 = ((System.Data.DataRowView)(row.DataItem)).Row["ID"].ToString().Trim();