主题：copyfile出现了问题

调试了很久也没有解决。在弹出的对话无论点击“是”还是“否”，都报错，什么问题啊？请教

目的：将项目目录下的文件复制到他目录，如果目录存在该文件，提示是否覆盖，不覆盖也要复制进去。

Dim ByCopyPath As String = ProjectPath & "\data.xls"

Dim dlg As New SaveFileDialog

dlg.Filter= "Excel文件|*.xls"

dlg.OverwritePrompt = False

If dlg.ShowDialog = DialogResult.Ok Then

    Dim ToCopyPath As String = dlg.FileName

    If FileSys.FileExists(ToCopyPath) Then

        Dim Result As DialogResult

        Dim waring1 As String = FileSys.GetName(ToCopyPath)

        Dim waring2 As String = """" & waring1 & """已经存在."

        Dim waring3 As String = vbcrlf & "你要覆盖原文件吗?"

        Dim waring As String = waring1 & waring2 & waring3

    Else

        FileSys.CopyFile(ByCopyPath,ToCopyPath)

    End If

End If