objective-c - iOS url encode问题

Question

有一个QueryString字符串，形如@"oauth_consumer_key=7w8q7wea43c0054d26958339d3413&oauth_nonce=9210314&oauth_signature_method=HMAC-SHA1&oauth_timestamp=1315591869"
我想对它进行url转义，用了stringByAddingPercentEncodingWithAllowedCharacters方法，但是其中的"="和"&"并没有被转义。为什么？

[querySting stringByAddingPercentEncodingWithAllowedCharacters:
                   [NSCharacterSet URLQueryAllowedCharacterSet]];

Answer 1

ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~:/?#[]@!$&'()*+,;=

According to what is said here, the above are all legal, including = and &

http://stackoverflow.com/a/1547940

Answer 2

The symbols mentioned by the question do not require URLEncode