path := 'C:/Users/admini/Desktop/vision1/1.bmp'
**//**：从后向前获取第一个字符“/”的下标
tuple_strrstr (path, '/', Position)
**//**：获取字符长度
tuple_strlen (path, Length)
**//**：截取指定起始下标到结束下标长度的字符串
tuple_substr (path, Position+1, Length-1, name)
