Public Function GetFileName(ByVal FilePathFileName As String) As String   '获取文件名  aaa.txt   
        On Error Resume Next
        Dim i As Integer, J As Integer
        i = Len(FilePathFileName)
        J = InStrRev(FilePathFileName, "/")
        GetFileName = Mid(FilePathFileName, J + 1, i)
    End Function
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        MsgBox(GetFileName("/dir1001/aaa.txt"))
    End Sub