python urllib.urlopen获得response后检查http响应头中的content type，,有时候在抓取到网页内容后

python urllib.urlopen获得response后检查http响应头中的content type，,有时候在抓取到网页内容后

有时候在抓取到网页内容后需要检查content-type，下面代码演示如何检查urllib.urlopen方法返回响应的http头

import urllibfrom types import *def iscontenttype(URLorFile,contentType='text'):    """    Return true or false (1 or 0) based on HTTP Content-Type.    Accepts either a url (string) or a "urllib.urlopen" file.    Defaults to 'text' type.    Only looks at start of content-type, so you can be as vague or precise    as you want.    For example, 'image' will match 'image/gif' or 'image/jpg'.    """    result = 1    try:        if type(URLorFile) == StringType:            file=urllib.urlopen(URLorFile)        else:            file = URLorFile        testType=file.info().getheader("Content-Type")        if testType and testType.find(contentType) == 0:            result=1        else:            result=0        if type(URLorFile) == StringType:            file.close()        return result    except:        return 0