ASP.NET Gridview 分页问题

Question

我有一个 gridview，它使用存储过程在代码隐藏中进行数据绑定。 我也在代码中处理分页事件，但每当我单击页码时，我都会不断获得空数据模板而不是更多行。 有什么建议么？

编辑：更改页面索引后，我将重新绑定 gv 的数据源。

这是我的代码 - 我有一个下拉列表，用于确定数据源是什么：

Protected Sub ddlProjectForm_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles ddlProjectForm.SelectedIndexChanged
    Dim strProjectFormID As String = Me.ddlProjectForm.SelectedValue
    Dim conn As New SqlConnection(WebConfigurationManager.ConnectionStrings("Conn").ConnectionString)
    Dim cmd As New SqlCommand()
    Dim da As New SqlDataAdapter
    Dim ds As New DataSet

    If strProjectFormID <> "Select" Then
        Try
            Using conn
                conn.Open()

                With cmd
                    .Connection = conn
                    .CommandType = CommandType.StoredProcedure
                    .CommandText = "sp_GetAllFormData"
                    .Parameters.AddWithValue("@projectFormID", strProjectFormID)
                End With

                da.SelectCommand = cmd
                da.Fill(ds)

                Me.gvAllSentData.DataSource = ds.Tables(0)
                Me.gvAllSentData.DataBind()
                Me.gvAllSentData.Visible = True
            End Using
        Catch sqlEx As SqlException
            Dim newError As New ErrorLogger(Me.Page.Title, sqlEx.Message, Session("UserName"))
            newError.LogError()

            Trace.Write(sqlEx.Message)
            Me.lblBadFeedback.Visible = True
            Me.lblBadFeedback.Text = "We're sorry - an error has occurred.  It has been logged and will be reviewed by the site admin."
        Catch ex As Exception
            Dim newError As New ErrorLogger(Me.Page.Title, ex.Message, Session("UserName"))
            newError.LogError()

            Trace.Write(ex.Message)
            Me.lblBadFeedback.Visible = True
            Me.lblBadFeedback.Text = "We're sorry - an error has occurred.  It has been logged and will be reviewed by the site admin."
        End Try
    Else
        Me.gvAllSentData.DataSource = Nothing
        Me.gvAllSentData.Visible = False
    End If

End Sub

Protected Sub gvAllSentData_PageIndexChanging(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewPageEventArgs) Handles gvAllSentData.PageIndexChanging
    Me.gvAllSentData.PageIndex = e.NewPageIndex
    Me.gvAllSentData.DataBind()
End Sub

Answer 1

您正在重新绑定一个空数据源。 您的代码应为：

Protected Sub gvAllSentData_PageIndexChanging(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewPageEventArgs) Handles gvAllSentData.PageIndexChanging
    Me.gvAllSentData.PageIndex = e.NewPageIndex
    Me.gvAllSentData.DataSource = __The_Data_To_Bind__
    Me.gvAllSentData.DataBind()
End Sub

Answer 2

尽管听起来很愚蠢，但您是否记得再次调用数据绑定代码？ 当分页发生时，会进行回发，并且 GridView 的数据源会丢失，因此您需要再次重新绑定数据，以便 GridView 可以根据页面加载适当的数据。

我认为这是我编写的第二个或第三个 ASP.NET 应用程序，然后我在编写代码时第一次记得重新数据绑定 8^D

Answer 3

这听起来确实像是一个数据绑定问题。 也许你的数据源在回发后是空的？

其他事件（例如排序）是否有效？

您能否在回发后单步执行代码的绑定部分并确认数据全部存在？

您有可以发布的代码吗？ 也许您应该创建一个测试工具，其中仅包含无法尝试跟踪问题的代码部分。