DataGrid动态生成问题，晕死了，高手帮帮忙~~~~~~~~~~~~~~~~

I cannot reproduce your problem, please post all the relevant code

源代码如下：
这是页面的基类：
Public Class Class1
    Inherits System.Web.UI.Page    Public WithEvents DataGrid1 As System.Web.UI.WebControls.DataGrid
    Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        DataGrid1 = New DataGrid()
        DataGrid1.EnableViewState = False        DataGrid1.AllowPaging = True
        DataGrid1.AllowSorting = True        Dim i As Integer = 0
        For i = 0 To Page.Controls.Count - 1
            If Page.Controls(i).GetType.Name = "HtmlForm" Then
                Page.Controls(i).Controls.Add(DataGrid1)
                Exit For
            End If
        Next        Me.DrawDataGrid()
        BindData()    End Sub'该函数用来绑定数据
    Protected Overridable Sub BindData()
        Dim dt As New DataTable()
        dt.Columns.Add("a", System.Type.GetType("System.String"))
        Dim row As DataRow = dt.NewRow()
        row.Item("a") = "aaaa"
        dt.Rows.Add(row)
        row = dt.NewRow()
        row.Item("a") = "bbbb"
        dt.Rows.Add(row)
        If Not Page.IsPostBack Then
            row = dt.NewRow()
            row.Item("a") = "bbbb"
            dt.Rows.Add(row)
            row = dt.NewRow()
            row.Item("a") = "cccc"
            dt.Rows.Add(row)
            row = dt.NewRow()
            row.Item("a") = "dddd"
            dt.Rows.Add(row)
        End If
        DataGrid1.DataSource = dt
        DataGrid1.DataBind()    End Sub'该函数用来画页角
    Private Sub DataGrid1_ItemCreated(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.DataGridItemEventArgs) Handles DataGrid1.ItemCreated
        Dim cb As CheckBox
        If e.Item.ItemType = ListItemType.Pager Then
            Dim totalPage As New Label()
            totalPage.Text = "第" & CInt(DataGrid1.CurrentPageIndex + 1) & "页/共" & DataGrid1.PageCount & "页      "
            e.Item.Cells(0).Controls.AddAt(0, totalPage)
            Dim gotoPage As New TextBox()
            gotoPage.Width = New Unit(30)
            e.Item.Cells(0).Controls.AddAt(1, gotoPage)
            Dim gotoBtn As New LinkButton()
            gotoBtn.Text = "GO"
            e.Item.Cells(0).Controls.AddAt(2, gotoBtn)
            Dim litSpace As New Literal()
            litSpace.Text = "            "
            e.Item.Cells(0).Controls.AddAt(3, litSpace)
        End If
    End Sub'该函数用来画DataGird的模版列
    Protected Sub DrawDataGrid()
        Dim FirstSort As String
        Dim Sort As String
        Dim DHorizontalAlign As String
        Dim ColumnWidth As String
        Dim col1 As New TemplateColumn()
        col1.ItemTemplate = New DataGridTemplate(ListItemType.Item, "CheckBox")
        DataGrid1.Columns.Add(col1)
    End Sub
    Private Class DataGridTemplate
        Implements ITemplate
        Dim templateType As ListItemType
        Dim columnName As String        Sub New(ByVal type As ListItemType, ByVal ColName As String)
            templateType = type
            columnName = ColName
        End Sub        Sub InstantiateIn(ByVal container As Control) _
           Implements ITemplate.InstantiateIn
            Dim lc As New Literal()
            Select Case templateType
                Case ListItemType.Header
                Case ListItemType.Item
                    Dim cb As New CheckBox()
                    container.Controls.Add(cb)
                Case ListItemType.EditItem
                Case ListItemType.Footer
            End Select
        End Sub
    End ClassEnd Class然后随便找个界面，继承class1，就行了

If Not Page.IsPostBack Then ..最好不用在函数里，应当用在page_load中

frankly, I am not clear myself, so don't be confused if you cannot understand what I am going to say, since I am yet to fully understand what is going on:TextBox/CheckBox/RadioButton are special, in that even if you set their EnableViewState to false, they can still keep their state. For example, you can add a button in the form<asp:Button id="Btn" runat="server" Text="Submit" />comment out
DataGrid1.AllowPaging = True
==>
'DataGrid1.AllowPaging = Truethen check the first checkbox, then click on Submit button, you can see that the first checkbox is still checked even if you rebind the whole thing!That means, even if you set the DataGrid's EnableViewState to false, the system still records these checkboxes' ViewState. If you don't believe me, open the HTML source in IE, and copy the value of the hidden control __VIEWSTATE to this page and click on "Parse ViewState" button, http://www.wilsondotnet.com/Demos/ViewState.aspxyou will see something like-1360000050
null
ArrayList
_ctl0:_ctl3:_ctl0
_ctl0:_ctl4:_ctl0
_ctl0:_ctl5:_ctl0
_ctl0:_ctl6:_ctl0
_ctl0:_ctl7:_ctl0and if you check the HTML source code, you will see they are exactly the names for those <input type=checkbox ..>Now, come back to the original question, what if you set DataGrid1.AllowPaging = True, and reduce the number of DataRows to 2? When the DataGrid is bound, everytime a row/cell is added to the control hierarchy, there are some catchupes to do, including invoking the Init/LoadViewState/ProcessPostData/Load event handler/method for the newly added control. So when you check the first checkbox, the check state will be restored along the way.When the Pager row is created/added, the system will know the third row (the Pager) is no longer valid according to the above ViewState, thus throws an exception. If you don't have DataGrid1.AllowPaging = True or have DataGrid1.AllowPaging = FALSE, the third row is never created/added and it will never check if the data is valid or not. Another way to verify is to create a FooterTemplate for DataGridTemplate and set ShowFooter= true, you will see the exact same errorsHow do you fix the problem? I wish you can clear the postdata stuffs, but I cannot find any such method, for now, you can do the following to cheat ASP.NET, :-)DataGrid1 = New DataGrid()
DataGrid1.ID = "DataGrid1" + DateTime.Now.ToString()

感谢思归，你所说的差不多我都明白了，用你的方法我也试成功了，我把Checkbox换成checkboxlist也行了，再次感谢你！

调试易

DataGrid动态生成问题，晕死了，高手帮帮忙~~~~~~~~~~~~~~~~

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