python判断对象是否为文件对象(file object)

# -*- coding: utf-8 -*- #@File name : filehelper.py #@Auther : GhostFromHeaven[csdn] #@date : 2012-07-19 import collections def isfilelike_r(f): """ Check if object 'f' is readable file-like that it has callable attributes 'read' and 'close' """ try: if isinstance(getattr(f, "read"), collections.Callable) \ and isinstance(getattr(f, "close"), collections.Callable): return True except AttributeError: pass return False def isfilelike_w(f): """ Check if object 'f' is readable file-like that it has callable attributes 'write' and 'close' """ try: if isinstance(getattr(f, "write"), collections.Callable) \ and isinstance(getattr(f, "close"), collections.Callable): return True except AttributeError: pass return False def isfilelike(f): """ Check if object 'f' is readable file-like that it has callable attributes 'read' , 'write' and 'closer' """ try: if isinstance(getattr(f, "read"), collections.Callable) \ and isinstance(getattr(f, "write"), collections.Callable) \ and isinstance(getattr(f, "close"), collections.Callable): return True except AttributeError: pass return False def fileinoutpattern(inp, out, callback=None, inmode="r", outmode="wb"): """ Make sure that 'inp' and 'out' has been 'converted' to file objects, and call 'callback' with them, finally clear it up. """ # Set up fin = inp if not isfilelike_r(fin): fin = open(inp, inmode) fout = out if not isfilelike_w(fout): fout = open(out, outmode) # Call the 'callback' result = None if callback != None: result = callback(fin, fout) # Clear up if not isfilelike_r(inp): fin.close() if not isfilelike_w(out): fout.close() return result