VB中检测当前文件目录下是否存在某文件

Private Sub Command1_Click()
Dim FS As Object, F, Fl As String
Set FS = CreateObject("Scripting.FileSystemObject")
If FS.FolderExists(App.Path & "\ABC") = True Then
F = App.Path & "\ABC"
Else
MsgBox "文件夹不存在！", 16, "´错误"
Exit Sub
End If
Fl = F & "\txt.txt"
If FS.FileExists(Fl) = True Then
MsgBox "这个文件存在！", 64, "文件存在"
Else
MsgBox "这个文件不存在！", 16, "错误"
End If
End Sub
这段代码你参考一下吧。我试过了，不错。

if DIR(文件路径）="" then
end
end if

if dir("c:\aaa.txt") ="" then