标题：Wrap.FindWindow 取得窗口句柄错误

Set Wrap = CreateObject("DynamicWrapper")
Wrap.Register "user32.dll","FindWindow","i=ss","f=s", "r=l"
WindowHandle = Wrap.FindWindow("", "无标题 - 记事本")
If WindowHandle=0 then
MsgBox "发现窗口"
Else
MsgBox "没发现"
End If 

WindowHandle = Wrap.FindWindow(vbNullString, "无标题 - 记事本")