Question

我的代码使用sqldataadapter和dataset填充DataGrid控件（vb.net 3.5框架），并通过其他控件的组合进行筛选。一切正常，除了RadioButtonList1在一个条件下有3个rbtns：

选择单选按钮1 @ index 0后，如果先前选择了rbtn 3 @ index 2并且它正确返回NO DATA，则会出现问题。
当先前选择了rbtn 3 @ index 2且它正确返回了SOME DATA时，不会发生这种情况。 radiobuttonlist选择的所有其他组合表现正确

我尝试使用sqldataadapter以不同的方式填充datagrid - 请参阅代码，包括使用存储过程（但如果我这样做，我无法自定义排序）。似乎没有什么能改变这种奇怪的行为。

我可能不得不求助于将单选按钮1更改为复选框控件并使用单独的绑定方法，如果没有人可以帮助我看到光。任何人都可以看到我遗失的任何明显事物吗？

ASPX（为简洁起见，datagrid仅显示2列）

<asp:radiobuttonlist   id="RadioButtonList1" runat="server" AutoPostBack="True" 
                            Font-Names="Arial" 
                            Font-Size="X-Small"   
                            BorderColor="Black" 
                            ForeColor="Black" 
                            RepeatDirection="Vertical" 
                            TextAlign="Right" CssClass="radioWithProperWrap" RepeatColumns="1"> 
                        <asp:ListItem Value="0" >All Projects</asp:ListItem> 
                        <asp:ListItem Value="1" Selected="True" >Sort By Project#</asp:ListItem> 
                        <asp:ListItem Value="2">Sort By Project Name</asp:ListItem>
</asp:radiobuttonlist>

<!--------------------
DataGrid1 
-------------------->            
<asp:datagrid  id="DataGrid1" runat="server"
                Font-Names="Tahoma,Sans Serif,arial" 
                Font-Size="Small" 
                ShowFooter="True" 
                DataMember="vwPersonSummary" 
                AllowSorting="True"
                OnPageIndexChanged="DataGrid1_Paging" Font-Bold="False" Font-Italic="False" Font-Overline="False" Font-Strikeout="False" Font-Underline="False" 
         UseAccessibleHeader="True" AutoGenerateColumns="False" 
         CssClass="nowrap" AllowPaging="True" PageSize="110" Visible="False"   >

                <FooterStyle HorizontalAlign="Right" Font-Bold="True" Font-Italic="False" 
                    Font-Overline="False" Font-Strikeout="False" Font-Underline="False"></FooterStyle>
                <SelectedItemStyle HorizontalAlign="Left" />
                <PagerStyle HorizontalAlign="Left" Mode="NumericPages" 
                    Position="TopAndBottom" PageButtonCount="75" />
                <AlternatingItemStyle BackColor="#EBF5FF"></AlternatingItemStyle>
                <headerStyle Font-Bold="True" Font-Italic="False" Font-Overline="False" 
                    Font-Size="Small" Font-Strikeout="False" Font-Underline="False" 
                    Width="12em" BackColor="#333333" ForeColor="White"  ></headerStyle>

                <ItemStyle Font-Size="Smaller" Width="12em" />

<Columns>

<asp:TemplateColumn HeaderText="Line#" FooterText="Line#">
                        <FooterStyle Font-Bold="True" Font-Italic="False" Font-Overline="False" Font-Strikeout="False" Font-Underline="False" HorizontalAlign="Center" 
                            Font-Names="Tahoma" Font-Size="Small" ForeColor="Black"  />
<headerStyle HorizontalAlign="Center" Font-Bold="True" Font-Italic="False" 
                            Font-Names="Tahoma" Font-Overline="False" Font-Size="Small" 
                            Font-Strikeout="False" Font-Underline="False" ForeColor="White"></headerStyle>
<ItemStyle HorizontalAlign="Left"></ItemStyle>
<ItemTemplate>
<%#(DataGrid1.PageSize * DataGrid1.CurrentPageIndex) + Container.ItemIndex + 1%> <!--generate row numbers-->
</ItemTemplate>
</asp:TemplateColumn>

<asp:BoundColumn DataField="Person" SortExpression="Employee" HeaderText="Person" >
  <FooterStyle Font-Bold="False" Font-Italic="False" Font-Overline="False" 
Font-Strikeout="False" Font-Underline="False" Wrap="False" />
  <headerStyle HorizontalAlign="Center" Font-Bold="True" Font-Italic="False" 
                            Font-Overline="False" Font-Size="Small" Font-Strikeout="False" 
                            Font-Underline="False" Wrap="False" Font-Names="Tahoma" 
                            ForeColor="White"  > </headerStyle>
  <ItemStyle   Font-Bold="False" Font-Italic="False" 
                            Font-Overline="False" Font-Strikeout="False" Font-Underline="False" 
                            HorizontalAlign="Left" Wrap="False"></ItemStyle>
</asp:BoundColumn>

<asp:BoundColumn DataField="Project#" SortExpression="Project#" HeaderText="Proj#">
  <FooterStyle Font-Bold="False" Font-Italic="False" Font-Overline="False" 
Font-Strikeout="False" Font-Underline="False" Wrap="False" />
  <headerStyle HorizontalAlign="Center" Font-Bold="True" 
Font-Italic="False" Font-Overline="False" Font-Strikeout="False" 
Font-Underline="False" Wrap="False" Font-Names="Tahoma" Font-Size="Small" 
ForeColor="White"  ></headerStyle>
  <ItemStyle Font-Bold="False" Font-Italic="False" Font-Overline="False" 
                            Font-Strikeout="False" Font-Underline="False" HorizontalAlign="Left" 
                            Wrap="False" />
</asp:BoundColumn>
</Columns>              
</asp:datagrid>

ASPX.VB（仅限相关代码）

  Sub BindData(ByVal strSortField As String)

        ''clear grid
        DataGrid1.DataSource = Nothing 'original

        ' TimeCodesSelected variable is populated based on Checkbox selections here. 
 ' Code removed for brevity.   

        Try
            ' Selected project 
            Dim ProjectSelected As String = Left(ddwnProjList.SelectedItem.Text, 7) 'Project#

            ' convert string dates to DateTime data types
            PPBegDate = Convert.ToDateTime(txtBegDate.Text)
            PPEndDate = Convert.ToDateTime(txtEndDate.Text)

            ' Check which radio button is selected 
            If RadioButtonList1.SelectedValue = 0 Then '0 = All projects

                ProjectSelected = String.Empty

'inline sql used to provide sort parameters to allow retaining sort order when paging through grid. sqlQuery is a global variable
                sqlQuery = "SELECT Person, Project# WHERE dtmDate BETWEEN '" & PPBegDate & "' AND '" & PPEndDate & "' " & TimeCodesSelected & " ORDER BY " & ViewState("sortField").ToString() & " " & ViewState("sortDirection").ToString()


                ''1=by number, or 2=by name
            Else
                sqlQuery = "SELECT Person, Project#, WHERE Project#='" & ProjectSelected & "' AND dtmDate BETWEEN '" & PPBegDate & "' AND '" & PPEndDate & "' " & TimeCodesSelected & " ORDER BY " & ViewState("sortField").ToString() & " " & ViewState("sortDirection").ToString()

                'Verify selected project exists, if not hide grid
                Dim blnRecordExists As Boolean

                Dim oRecord As DataAccessLib.SqlConn = New DataAccessLib.SqlConn()
                blnRecordExists = oRecord.VerifyProjectExists(ProjectSelected, PPBegDate, PPEndDate)

                If (blnRecordExists = True) Then
                    DataGrid1.Visible = True
                    lblErrorMsg.Text = Nothing
                Else
                    DataGrid1.Visible = False
                    lblErrorMsg.Text = "No records found for this project number during selected dates."
                End If
            End If

            Using conn As SqlConnection = New SqlConnection(conStr)
                Using cmd As New SqlCommand(sqlQuery, conn)
                    cmd.CommandType = CommandType.Text
                    Using sda As New SqlDataAdapter(cmd)
                        Using ds As New DataSet()
                            sda.Fill(ds)
                            DataGrid1.DataSource = ds.Tables(0)
                        End Using
                    End Using
                End Using

''Orignal code that works as well and also has the switch from index 2 to index 0 issue 
'SqlDataAdapter1.Fill(DsDetailByProj1, "vwPersonSummary") 
'Dim objDataView As DataView = DsDetailByProj1.Tables("vwPersonSummary").DefaultView
'DataGrid1.DataSource = objDataView
                DataGrid1.DataBind()

            End Using 'end using closes conn and goes before 'Catch' 

        Catch ex As SqlException
            sqlErrorMsg = sqlErrorMsg + ": " + ex.Message.ToString
            lblErrorMsg.Visible = True
            lblErrorMsg.Text = sqlErrorMsg

        Catch e As Exception
            'reset grid to 1st page after grid refresh (databind)
            DataGrid1.CurrentPageIndex = 0


        Finally 'the using statement closes objects.  Kept here for reference only.
            ''close and dispose of database connection
            'SqlConnection1.Close()
            'SqlConnection1.Dispose()

            ''close sqldatadapter if applicable  
            'SqlDataAdapter1.Dispose()
        End Try

    End Sub
Protected Sub RadioButtonList1_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs) Handles RadioButtonList1.SelectedIndexChanged

        If RadioButtonList1.SelectedValue = 0 Then
            ddwnProjList.Enabled = False 

        Else 'if 1 or 2
            ddwnProjList.Enabled = True

        End If

        GetProjectList()'fills ddwnProjList by Project Number or Project Name

        BindData("dtmDate")  

    End Sub
Private Sub ddwnProjList_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ddwnProjList.SelectedIndexChanged

        If (ViewState("sortField") <> Nothing) Then
            BindData(ViewState("sortField").ToString())
        Else
            BindData("dtmDate")
        End If

    End Sub

enter code here

Answer 1

正如我在评论中提到的，将DataGrid的visibility属性设置为true是解决此问题的第一步。

然后我使用Scott Mitchell的回答here来验证网格是否为空。通过消除对数据库的另一次往返的需要，这似乎比我的方式更有效。

       If (DataGrid1.Items.Count = 0) Then
            lblNoRecordsMessage.Text = "Yo Adrian, there are no records for the selected dates."
            lblNoRecordsMessage.Visible = True
            DataGrid1.Visible = False
        Else
            lblNoRecordsMessage.Text = Nothing
            lblNoRecordsMessage.Visible = False
            DataGrid1.Visible = True
        End If

我还确保DataBrid和Label在DataBind（）方法的开头设置为可见，因为在最后一次数据绑定之后它有可能被置于不可见状态。

        lblNoRecordsMessage.Text = Nothing
        lblNoRecordsMessage.Visible = False
        DataGrid1.Visible = True

vb.net radiobuttonlist包含3个按钮，当在一个条件下从索引2转换为0时，不触发

1 个答案: