SelectedValue of DropDownlList

Question

我有一个在编辑部分有下拉列表的网格视图，我想在编辑时绑定从数据库中选择的值。在designer部分中，没有SelectedValue属性，它会给出运行时错误。有什么可以帮忙的？？有什么办法从代码背后处理吗？

<asp:TemplateField HeaderText="Company">
                <EditItemTemplate>
                    <asp:DropDownList ID="DDLCompany" runat="server" DataValueField="cname" DataTextField="cname" SelectedValue = '<%# Bind("cname") %>'  >
                    </asp:DropDownList>
                </EditItemTemplate>
                <ItemTemplate>
                <asp:Label ID="CompanyLabel" runat="server" Text='<%# Bind("cname") %>'></asp:Label>
                </ItemTemplate>   
             </asp:TemplateField>

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
            DropDownList DDLCompany = (DropDownList)e.Row.FindControl("DDLCompany");
            DropDownList DDLPrinter = (DropDownList)e.Row.FindControl("DDLPrinter");

            if (DDLCompany != null)
            {
                DDLCompany.DataSource = userobj.FetchCompanyList();
                DDLCompany.DataBind();
                DDLCompany.SelectedValue = GridView1.DataKeys[e.Row.RowIndex].Values[0].ToString();                
            }

            if (DDLPrinter != null)
            {
                DDLPrinter.DataSource = userobj.FetchPrinterList();
                DDLPrinter.DataBind();
                DDLPrinter.SelectedValue = GridView1.DataKeys[e.Row.RowIndex].Values[0].ToString();
            }
        }
    } 

Answer 1

在代码后面的

• 在找到您的Dropdwonlist之前，您必须检查e.Row.RowType== DataControlRowType.DataRow & e.Row.RowState == DataControlRowState.Edit in RowDataBound。您可以通过以下方式设置选择值：http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.gridviewrow.dataitem.aspx
• On http://msdn.microsoft.com/en-us/library/ms178294.aspx