django url 验证正则表达式 (来源):

import re
regex = re.compile(
        r'^(?:http|ftp)s?://' # http:// or https://
        r'(?:(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?.)+(?:[A-Z]{2,6}.?|[A-Z0-9-]{2,}.?)|' #domain...
        r'localhost|' #localhost...
        r'd{1,3}.d{1,3}.d{1,3}.d{1,3})' # ...or ip
        r'(?::d+)?' # optional port
        r'(?:/?|[/?]S+)$', re.IGNORECASE)

print(re.match(regex, "http://www.example.com") is not None) # True
print(re.match(regex, "example.com") is not None)            # False