asp.net – 如何在Gridview中绑定DropDownList,而不是从gridview绑定数据

获得答案的一半是知道如何提出问题.我不确定我做得很好,但这是我最好的一击.

我正在尝试将ddl与gridview中的数据绑定,而不是来自gridview本身.这是在EditItemTemplate中.这样做的目的是让用户从查找存储过程开始选择值和一系列其他值.

我在这里提到我之前已成功完成此操作但使用了ObjectDataSource.我这次试图避免这种情况,现在完全从后面的代码中完成,然后将其移到数据层.

这是我到目前为止所拥有的……

<asp:GridView ID="usersGrid" runat="server"                 
        DataKeyNames="userID" 
        AutoGenerateColumns="false" Width="580" 
        OnRowUpdating="usersGrid_RowUpdating"
        OnRowEditing="usersGrid_RowEditing" 
        OnRowCancelingEdit="usersGrid_RowCancelingEdit"                                   OnRowDeleting="usersGrid_RowDeleting" 
        >

…

<EditItemTemplate>
                <div class="gridName">
                    <asp:TextBox ID="txtFirstName" Text='<%#Eval("firstName") %>' runat="server" Width="95" />
                </div>
                <div class="gridName">
                    <asp:TextBox ID="txtLastName" Text='<%#Eval("lastName") %>' runat="server" Width="95" />
                </div>
                <div class="gridEmail">
                    <asp:TextBox ID="txtEmail" Text='<%#Eval("email") %>' runat="server" Width="245" />
                </div>
                <div class="gridName">
                    <asp:DropDownList ID="ddl_GetLists" 
                    DataSourceID="GetListData()"
                    AppendDataBoundItems="true"
                    DataValueField="listID"
                    DataTextField="listName"
                    SelectedValue='<%#Bind("listID") %>'
                    runat="server"
                    >
                    </asp:DropDownList>
                </div>
            </EditItemTemplate>

….

Protected Sub usersGrid_RowEditing(ByVal sender As Object,ByVal e As GridViewEditEventArgs)
    usersGrid.EditIndex = e.NewEditIndex
    BindData()

End Sub

….

Private Sub BindData()
    Dim conn As New sqlConnection(connectionString)
    Dim ad As New sqlDataAdapter("MAINT_disT_GET_USERS",conn)
    Dim ds As New DataSet()
    ad.Fill(ds)
    GetListData()
    usersGrid.DataSource = ds
    usersGrid.DataBind()

End Sub

我包括了最后两个以及我尝试过但失败的其他方法.

…

Protected Sub usersGrid_RowDataBound(ByVal sender As Object,ByVal e As GridViewRowEventArgs)
    If e.Row.RowState = DataControlRowState.Edit Then
        Dim ddl As DropDownList = DirectCast(e.Row.FindControl("ddl_GetLists"),DropDownList)

        Dim conn As New sqlConnection(connectionString)
        Dim ad As New sqlDataAdapter("MAINT_disT_GET_LISTS",conn)
        Dim ds As New DataSet()
        ad.Fill(ds)

        ddl.DataSource = ds
        ddl.DataBind()
    End If
End Sub

Public Function BindDropdown() As DataSet
    Dim conn As New sqlConnection(connectionString)
    Dim ad As New sqlDataAdapter("MAINT_disT_GET_LISTS",conn)
    Dim ds As New DataSet()
    ad.Fill(ds)

    ddl_GetLists.DataSource = ds
    ddl_GetLists.DataBind()
End Function

我还会问,为什么在最终函数中,为什么控件ddl_GetLists也不被识别？在网格内部,它从设计器中消失,但在网格之外再次出现.

感谢大家的帮助.

解决方法

你有几个选择.您可以使用数据源控件,也可以在GridView的RowDataBound事件中绑定代码隐藏中的下拉列表.

我注意到你的代码中也存在一些问题.在您的示例中,您错误地分配了DataSourceID. DataSourceID应指向页面上数据源控件的ID：

<asp:DropDownList ID="ddl_GetLists"     
    DataSourceID="sqlDataSource1"    
    AppendDataBoundItems="true"    
    DataValueField="listID"    
    DataTextField="listName"    
    SelectedValue='<%#Bind("listID") %>'    
    runat="server">    
</asp:DropDownList>

<asp:sqlDataSource ID="sqlDataSource1" runat="server"                  
    ConnectionString="<%$ConnectionStrings:ConnectionString %>"                  
    SelectCommand="SELECT listID,listName FROM SoMetable">                                             
</asp:sqlDataSource>

如果要在代码隐藏中进行绑定,可以通过RowDataBound事件执行此操作：

Protected Sub GridView1_RowDataBound(sender As Object,e As GridViewRowEventArgs)
    If e.Row.RowType = DataControlRowType.DaTarow AndAlso (e.Row.RowState And DataControlRowState.Edit) = DataControlRowState.Edit Then
        Dim ddl As DropDownList = TryCast(e.Row.FindControl("ddl_GetLists"),DropDownList)
        If ddl IsNot nothing Then
            ddl.DataSource = RetrieveDataSource()
            ddl.DataBind()
        End If
    End If
End Sub