html页面一般都会指定一个编码，如何获取到是处理html页面的第一步，因为错误的编码必然带来后面处理的问题。这里我用python的正则表达式写了个：

import re a = ["<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />", '<meta http-equiv=Content-Type content="text/html;charset=gb2312">', '<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">', '<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />', '<meta http-equiv="content-type" content="text/html; charset=utf-8" />', '<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />', '<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />' ] b = "<meta[ ]+http-equiv=["']"']"']?text/html;[ ]*charset=([0-9-a-zA-Z]+)["']" B = re.compile(b, re.IGNORECASE) for ax in a: r1 = B.search(ax) if r1: print r1.group() print r1.group(1), len(r1.group()) else: print 'not match'