为什么这个程序的 Grid1 总是显示变量未定义？求高手指教

Private Sub CmdPrint_Click()
 Dim ex As Excel.Application
    Dim a As String
    Dim i As Integer, j As Integer
    
    On Error Resume Next
    
 
    If Grid1.Rows < 3 Then
        Exit Sub
    End If
    
    If MsgBox("是否进行打印？", vbYesNo, "报表打印") = vbNo Then
        Exit Sub
    End If
    
    CmdPrint.Enabled = False
    cmdQuery.Enabled = False
    cmdClear.Enabled = False
    SetTipInfo ("正在生成报表,请等待")
    
    Set ex = New Excel.Application
    
    ex.Workbooks.Add
    
    ex.Range("A1:" & Chr(Asc("A") + Grid1.Cols - 1) & "1").Select
    With ex.Selection
        .MergeCells = True
        .HorizontalAlignment = xlCenter
        .VerticalAlignment = xlBottom
        .Font.Bold = True
        .Font.Name = "宋体"
        .Font.Size = 14
        .Borders(xlEdgeLeft).LineStyle = xlContinuous
        .Borders(xlEdgeTop).LineStyle = xlContinuous
        .Borders(xlEdgeRight).LineStyle = xlContinuous
        .Borders(xlEdgeBottom).LineStyle = xlContinuous
    End With
    ex.Range("A1").Value = CStr(Lu) & "#炉" & TabStrip1.SelectedItem.Caption & "报表"
 
    ex.Range("A2:" & Chr(Asc("A") + Grid1.Cols - 1) & CStr(Grid1.Rows)).Select
    With ex.Selection
            .Borders(xlDiagonalDown).LineStyle = xlNone
            .Borders(xlDiagonalUp).LineStyle = xlNone
            .Borders(xlEdgeLeft).LineStyle = xlContinuous
            .Borders(xlEdgeTop).LineStyle = xlContinuous
            .Borders(xlEdgeRight).LineStyle = xlContinuous
            .Borders(xlEdgeBottom).LineStyle = xlContinuous
            .Borders(xlInsideVertical).LineStyle = xlContinuous
            .Borders(xlInsideHorizontal).LineStyle = xlContinuous
            .Font.Size = 10
    End With    With ex
        For i = 0 To Grid1.Rows - 2
            For j = 65 To Grid1.Cols + 65
                .Range(Chr(j) & CStr(i + 2)).Value = Grid1.TextMatrix(i, j - 65)
                DoEvents
            Next
        Next
    End With
    
    If TabStrip1.SelectedItem.Key = "高压历史参数" Then
        ex.Columns("A:A").ColumnWidth = 15 '日期
        ex.Columns("B:B").ColumnWidth = 15 '时间
        ex.Columns("C:C").ColumnWidth = 15 '除尘器名称
        ex.Columns("D:D").ColumnWidth = 15 '室
        ex.Columns("E:E").ColumnWidth = 15 '电场
        ex.Columns("C:C").ColumnWidth = 15 '运行状态
        ex.Columns("K:K").ColumnWidth = 4.5 '油温
        ex.Columns("L:L").ColumnWidth = 4.5 'IGBT温度
        ex.Columns("M:M").ColumnWidth = 4.5 '闪频
    Else
        ex.Columns("A:A").ColumnWidth = 15 '日期
        ex.Columns("B:B").ColumnWidth = 20 '设备名称
        ex.Columns("G:G").ColumnWidth = 30 '故障描述
        
    End If
    '设置页边距
    With ex.ActiveSheet.PageSetup
        .LeftMargin = Application.InchesToPoints(0.196850393700787)
        .RightMargin = Application.InchesToPoints(0.196850393700787)
        .TopMargin = Application.InchesToPoints(0.196850393700787)
        .BottomMargin = Application.InchesToPoints(0.196850393700787)
        .CenterHorizontally = True
    End With
    ex.Visible = True
   
    ex.ActiveWorkbook.Saved = True
    ex.Quit
    Set ex = Nothing
    
    SetTipInfo ("打印完毕")
    CmdPrint.Enabled = True
    cmdQuery.Enabled = True
    cmdClear.Enabled = True
End Sub