Question

我无法确定导致编辑命令失败的问题

GridView代码

<asp:GridView ID="GridView1" runat="server" AllowPaging="True" 
    AllowSorting="True" AutoGenerateColumns="False" CellPadding="4" 
    DataKeyNames="Requestid" DataSourceID="SqlDataSource1" ForeColor="#333333" 
    GridLines="None" Height="321px" Width="604px">
    <AlternatingRowStyle BackColor="White" />
    <Columns>
     <asp:CommandField ShowEditButton="True"  UpdateText="Submit" />
        <asp:BoundField DataField="Requestid" HeaderText="Requestid" ReadOnly="True" 
            SortExpression="Requestid" />
        <asp:BoundField DataField="Receiveddate" HeaderText="Receiveddate" 
            SortExpression="Receiveddate" />
        <asp:BoundField DataField="Ctname" HeaderText="Ctname" 
            SortExpression="Ctname" />
        <asp:TemplateField HeaderText="Requestor" SortExpression="Requestor">
            <EditItemTemplate>
                <asp:DropDownList ID="DropDownList1" runat="server" 
                    DataSourceID="SqlDataSource2" DataTextField="analystname" 
                    DataValueField="contact_id" SelectedValue='<%# Bind("Requestor") %>'>
                </asp:DropDownList>
                <asp:SqlDataSource ID="SqlDataSource2" runat="server" 
                    ConnectionString="<%$ ConnectionStrings:Customers %>"         SelectCommand="SELECT [contact_id], [first_name]+ space(1)+ [last_name] as analystname FROM [contact]
order by contact_id"></asp:SqlDataSource>
            </EditItemTemplate>
            <ItemTemplate>
                <asp:Label ID="Label1" runat="server" Text='<%# Bind("Requestor") %>'></asp:Label>
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
    <EditRowStyle BackColor="#CC3300" />
    <FooterStyle BackColor="#507CD1" Font-Bold="True" ForeColor="White" />
    <HeaderStyle BackColor="#CBB06D" Font-Bold="True" ForeColor="White" />
    <PagerStyle BackColor="#2461BF" ForeColor="White" HorizontalAlign="Center" />
    <RowStyle BackColor="#EFF3FB" />
    <SelectedRowStyle BackColor="#D1DDF1" Font-Bold="True" ForeColor="#333333" />
    <SortedAscendingCellStyle BackColor="#F5F7FB" />
    <SortedAscendingHeaderStyle BackColor="#6D95E1" />
    <SortedDescendingCellStyle BackColor="#E9EBEF" />
    <SortedDescendingHeaderStyle BackColor="#4870BE" />
</asp:GridView>

<asp:SqlDataSource ID="SqlDataSource1" runat="server" 
    ConnectionString="<%$ ConnectionStrings:Customers %>" SelectCommand="SELECT RR.Requestid,Convert(varchar(20),RR.Receiveddate,100) as Receiveddate,RR.Ctname,C.First_Name +Space(1) + C.Last_NAME as Requestor  from report_request_draft RR inner join Contact C on RR.requestor = C.contact_id
where clonedfromid is not null"

UpdateCommand="UPDATE [REPORT_REQUEST_DRAFT] SET  [REQUESTOR] = @Requestor  WHERE [requestid] = @requestid">

</asp:SqlDataSource>

当我点击编辑命令按钮时，它会给我以下错误

错误

'DropDownList1'有一个SelectedValue，它是无效的，因为它在项目列表中不存在。参数名称：value 描述：执行当前Web请求期间发生未处理的异常。请查看堆栈跟踪以获取有关错误及其源自代码的位置的更多信息。

异常详细信息：System.ArgumentOutOfRangeException：'DropDownList1'具有SelectedValue，该ListValue无效，因为它在项列表中不存在。参数名称：值

Answer 1

DropDownList不能以这种方式绑定。通过使用SelectedValue绑定，它需要在GridView绑定之前绑定DropDownList，但这是逻辑上不可能的，因为DropDownList无法绑定，直到GridView完成其绑定。您应该将此逻辑放在RowDataBound事件后面的代码中。此时，您应手动绑定DropDownList，然后设置其SelectedValue属性。

Answer 2

考虑以下链接，它将帮助您解决问题，还会向您展示如何在网格视图中完美地绑定 EditItemTemplet 。我强制您使用this链接以更好地理解网格视图。

在gridview中编辑命令错误输出

2 个答案: