Question

我在DropDownList内使用3 DataList。因此，每行包含3 DropDownList。 DataList还包含DataKeyField。

现在，如果用户从DropDownList1中选择值，那么我想绑定DropDownList2，如果用户从DropDownList2中选择值，那么我想绑定DropDownList3。我使用的是SelectedIndexChanged，我可以获得相关DropDownList所选值的值。但是，如果用户选择DropDownList2，那么我还需要DropDownList1的值，并且还需要尊重DataKeyField的值。

怎么弄这个？

我的代码示例：

<asp:DataList ID="dlTest" runat="server" OnItemDataBound="dlTest_ItemDataBound"
        DataKeyField="TestId">
<ItemTemplate>
<asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="true" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged"> </asp:DropDownList>
<asp:DropDownList ID="DropDownList2" runat="server" AutoPostBack="true" OnSelectedIndexChanged="DropDownList2_SelectedIndexChanged"> </asp:DropDownList>
<asp:DropDownList ID="DropDownList3" runat="server" AutoPostBack="true" OnSelectedIndexChanged="DropDownList3_SelectedIndexChanged"> </asp:DropDownList>
</ItemTemplate>
</asp:DataList>

在此onSelectedIndexChanged DropDownList3，我能够获得它的选择值，但我还需要尊重行DropDownList1和DropDownList2的所选值，以及尊重DataKeyField值。

protected void DropDownList3_SelectedIndexChanged(object sender, EventArgs e)
    {
        var DropDownList3 = (DropDownList)sender;

        string DDL3 = ((DropDownList)DropDownList3.NamingContainer.FindControl("DropDownList3")).SelectedValue;
        // Also need selectedValue of DropDownList1 and DropDownList2 and DataKeyField.
    }

Answer 1

我想你差不多了。你只需要。使用您的代码：

protected void DropDownList3_SelectedIndexChanged(object sender, EventArgs e)
{

    var DropDownList1 = (DropDownList)sender;
    var DropDownList2 = (DropDownList)sender;
    var DropDownList3 = (DropDownList)sender;

    string DDL1 = ((DropDownList)DropDownList1.NamingContainer.FindControl("DropDownList1")).SelectedValue;
    string DDL2 = ((DropDownList)DropDownList2.NamingContainer.FindControl("DropDownList2")).SelectedValue;
    string DDL3 = ((DropDownList)DropDownList3.NamingContainer.FindControl("DropDownList3")).SelectedValue;
}

无论哪种方式，我都会这样做：

    item valueddl1 = DropDownList1.SelectedValue;

等等;它应该像weel一样工作，而且更简单一点。

根据DataList中的另一个Dropdown SelectedValue绑定一个下拉列表 - c＃

1 个答案: