C# GridView的OnRowDataBound事件中处于编辑模式的GridView行

以下是如何做到这一点：

在标记中，向

GridView

的OnStatBound添加一个方法：

<asp:GridView ID="GridView1" runat="server" CellPadding="4" ForeColor="#333333" GridLines="None"
    ... ... ...
    OnRowDataBound="GridView1_RowDataBound" >

---

我让它执行类似于上面的操作，但当我尝试设置SelectedValue=''时，我得到错误：“'selResolutionCategory'有一个SelectedValue，该值无效，因为它不存在于项目列表中。”但我知道它确实存在，通过查询数据库，无法只执行类似于上面的操作（这适用于文本框）据我所知并非如此。有同样的问题。这就是为什么我制作了一个标签-将其visible属性设置为false，然后使用ddlDropDownList.SelectedValue=lblLabel.Text；我厌倦了处理它，知道这会起作用。我如何使用上面的完整代码来实现这一点？我使用绑定字段和模板字段进行编辑。看看下面的我给了你我的asp的完整代码。你必须像我那样使用TemplateField。

protected void gvVehicle_OnRowDataBound(object sender, GridViewRowEventArgs e)
    {
        foreach (GridViewRow gvr in gvVehicleTEMP.Rows)
        {
            DropDownList ddlLocation = ((DropDownList)gvr.FindControl("ddlLocation"));
            Label lblLocationLabel = ((Label)gvr.FindControl("lblLocationLabel"));

            conn.Close();
            conn.Open();

            SqlCommand cmdLocationNames = new SqlCommand("SELECT Name FROM Billers WHERE Store = '" + 1 + "' ORDER BY Name ASC", conn);
            List<string> internalLocationsList = new List<string>();

            using (SqlDataReader reader = cmdLocationNames.ExecuteReader())
            {
                while (reader.Read())
                {
                    string interlocations = reader.GetString(0);
                    internalLocationsList.Add(interlocations);
                }
                foreach (string locname in internalLocationsList)
                {
                    ddlLocation.Items.Add(new ListItem(locname));
                    conn.Close();
                }
                conn.Close();
            }

            conn.Close();

        }

  //EDIT: if (lblLocationLabel.Text.Length > 0)
            {
                 ddlLocation.SelectedValue = lblLocationLabel.Text;
            }
    }  

protected void gvVehicle_OnRowDataBound(object sender, GridViewRowEventArgs e)
    {
        foreach (GridViewRow gvr in gvVehicleTEMP.Rows)
        {
            DropDownList ddlLocation = ((DropDownList)gvr.FindControl("ddlLocation"));
            Label lblLocationLabel = ((Label)gvr.FindControl("lblLocationLabel")); //add this line to find the label

            conn.Close();
            conn.Open();

            SqlCommand cmdLocationNames = new SqlCommand("SELECT Name FROM Billers WHERE Store = '" + 1 + "' ORDER BY Name ASC", conn);
            List<string> internalLocationsList = new List<string>();

            using (SqlDataReader reader = cmdLocationNames.ExecuteReader())
            {
                while (reader.Read())
                {
                    string interlocations = reader.GetString(0);
                    internalLocationsList.Add(interlocations);
                }
                foreach (string locname in internalLocationsList)
                {
                    ddlLocation.Items.Add(new ListItem(locname));
                    conn.Close();
                }
                conn.Close();
            }

            conn.Close();

        }

      if (lblLocationLabel.Text.Length > 0)//Added if statement
            {
                 ddlLocation.SelectedValue = lblLocationLabel.Text;
            }
    } 

<asp:TemplateField HeaderText="Location" SortExpression="Received">
           <ItemTemplate>
                  <asp:DropDownList ID="ddlLocation" runat="server" AutoPostBack="false">
                  </asp:DropDownList>
                  <asp:Label ID="lblLocationLabel" runat="server" Text='<%# Bind("Location") %>' Visible="false"></asp:Label>
                              <font size="2">Received On: </font>
           </ItemTemplate>
           <HeaderStyle Width="200px" />
</asp:TemplateField>

<asp:TemplateField HeaderText="Severity">
 <HeaderStyle HorizontalAlign="Left" />
 <ItemTemplate>
   <%# Eval("ResolutionSeverity")%>
 </ItemTemplate>

 <EditItemTemplate>
   <asp:DropDownList  ID="selResolutionSeverity" runat="server"
     DataSourceID="dsSeverities"
     DataTextField="Description"
     DataValueField="ID"
     SelectedValue='<%# Bind("ResolutionSeverity") %>'  />
 </EditItemTemplate>
</asp:TemplateField>

<asp:GridView ID="GridView1" runat="server" CellPadding="4" ForeColor="#333333" GridLines="None"
    ... ... ...
    OnRowDataBound="GridView1_RowDataBound" >

protected void GridView1_RowDataBound(object sender, System.Web.UI.WebControls.GridViewRowEventArgs e)
{
    //Make sure the row is in edit mode to find controls in EditItemTemlates
    if ((e.Row.RowType == DataControlRowType.DataRow) && ((e.Row.RowState & DataControlRowState.Edit) > 0))
    {

        var ddl = GridView1.FindControl("selResolutionSeverity") as DropDownList;
        if (ddl != null)
        {

            // Consider using parameterized query to prevent possible sql injection
            string sSQL = @"SELECT ErrorTypeLookupID as Value, ErrorDescription as DisplayText
                            FROM BabelFish.dbo.ErrorTypeLookup (NOLOCK)
                            WHERE ErrorType = 'Severity' ";

            DataSet DS = new DatabaseAccessing.DatabaseConnection().DS(sSQL);
            ddl.DataSource = DS;
            ddl.DataTextField = "DisplayText";
            ddl.DataValueField = "Value";
            ddl.DataBind();
            ddl.Items.Insert(0, new ListItem("-- Select --", "0"));
        }
    }
}