从全路径名中提取文件名 
Function StripPath(T$) As String
Dim x%, ct%
StripPath$ = T$
x% = InStr(T$, "\")
Do While x%
ct% = x%
x% = InStr(ct% + 1, T$, "\")
Loop
If ct% > 0 Then StripPath$ = Mid$(T$, ct% + 1)
End Function
例子：
File = StripPath("c:\windows\hello.txt"