"Oswaldo" <Oswaldo@discussions.microsoft.com> wrote in message
news:3C113AE5-6616-46B6-AA1B-F9ADC8D6E5F8@microsoft.com...
> Hello, I have a problem. I want to Preselecting an Item in a Drop-Down
List
> inside a datagrid but I have an error. Show me "Object reference not set
to
> an instance of an object." in DataGrid1_ItemDataBound event in the code
"Dim
> currentgenre As String = CType(drv("cod_estado"), String)". I send the
html
> and codebehind code.
>
> Please help me in this.
>
> Regards,
> Oswaldo
>
>
> HTML
> --------------------------------------------------------------------------
------------------
> <asp:DataGrid id="DataGrid1" style="Z-INDEX: 101; LEFT: 224px; POSITION:
> absolute; TOP: 152px" runat="server">
> <Columns>
> <asp:TemplateColumn>
> <HeaderTemplate>
> <asp:Label id=Label1 runat="server" Text="<%# Container.DataItem %>">
> </asp:Label>
> </HeaderTemplate>
> <ItemTemplate>
> <asp:DropDownList id=DropDownList1 runat="server" Width="120px"
> DataTextField="descripcion" DataSource="<%#LlenarCombo() %>"
> DataValueField="cod_estado">
> </asp:DropDownList>
> </ItemTemplate>
> </asp:TemplateColumn>
> </Columns>
> </asp:DataGrid>
>
> CODEBEHIND
> --------------------------------------------------------------------------
--------------
> Private Sub Page_Load(ByVal sender As System.Object, ByVal e As
> System.EventArgs) Handles MyBase.Load
> 'Introducir aquí el código de usuario para inicializar la página
> Dim da1 As New SqlDataAdapter("select top 10
> cod_orden,razon_social,estado from orden", SqlConnection1)
> da1.Fill(ds, "Ordenes")
> DataGrid1.DataSource = ds.Tables("Ordenes")
> DataGrid1.DataBind()
> End Sub
> Public Function LlenarCombo() As DataTable
> If Application("estados") Is Nothing Then
> Dim da1 As New SqlDataAdapter("select cod_estado,descripcion
> from estados", SqlConnection1)
> da1.Fill(ds, "Estados")
> Application("estados") = ds.Tables("Estados")
> Return ds.Tables("Estados")
> Else
> Return CType(Application("estados"), DataTable)
> End If
> End Function
>
> Private Sub DataGrid1_ItemDataBound(ByVal sender As Object, _
> ByVal e As System.Web.UI.WebControls.DataGridItemEventArgs) _
> Handles DataGrid1.ItemDataBound
> If ((e.Item.ItemType = ListItemType.Item) Or (e.Item.ItemType =
> ListItemType.AlternatingItem) Or (e.Item.ItemType = ListItemType.Header))
Then
> Dim drv As DataRowView = CType(e.Item.DataItem, DataRowView)
> Dim currentgenre As String = CType(drv("cod_estado"), String)
> Dim ddl As New DropDownList
> ddl = CType(e.Item.FindControl("DropDownList1"), DropDownList)
> ddl.SelectedIndex =
> ddl.Items.IndexOf(ddl.Items.FindByValue(currentgenre))
> End If
> End Sub