主题：求助

此主题相关图片如下：qwe.png

老师，我这个窗体默认的打开不让它显示数据，等查询后再显示查询结果

我现在实现 这个“打印”在没有点查询，查询结果出来之前，点“打印”的时候，提示先查询

打印的代码如下，可是不起作用，请老师指点

If Tables("零配件采购汇总_Table1").Current Is Nothing Then
    MessageBox.Show("请先点查询","提示")
    Return
Else
    Dim pg As WinForm.SplitPanel = Forms("零配件采购汇总").Controls("SplitContainer1").Panel2
    Dim doc As PrintDoc = e.Form.GernatePrintDoc(pg)
    For Each c As object In Doc.Body.Children
        If Typeof c Is prt.RenderTable Then
            Dim t As prt.RenderTable = c
            For i As Integer = 0 To t.Rows.count-1
                For j As Integer = 0 To t.Cols.count-1
                    t.cells(i,j).Style.BackColor = Color.white
                    t.cells(i,j).Style.TextColor = Color.black
                Next
            Next
        End If
    Next
    doc.Preview()
End If