對於https的網絡請求很多人都比較頭疼，不止iOS包括pc端和移動端的很多請求都離不開https
CFNetwork SSLHandshake failed (-9806)
error = Error Domain=NSURLErrorDomain Code=-1202 "The certificate for this server is invalid. You might be connecting to a server that is pretending to be “192.168.10.16” which could put your confidential information at risk."
遇到以上錯誤的請舉手，沒錯這就是臭名昭著的https請求出現的錯誤。歸結原因證書原因。但是如何設置呢，你會發現百度一下子廢物了。現在就從iOS原生的網絡請求着手解決這一問題.
研究了一下NSURLConnection這個類會發現一下兩個代理
- (BOOL)connection:(NSURLConnection*)connection canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace*)protectionSpace
- (void)connection:(NSURLConnection*)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge*)challenge
沒錯，iOS本身提供了對於https請求證書的設置，就在代理方法裏。現在ok了，只要解決了代理的設置就可以完成完整的https請求首先做好數據請求的相關準備
接着設置證書權限問題
看一下控制檯輸出
2013-11-02 14:07:07.719 HttpsRequest[485:70b] didReceiveAuthenticationChallenge NSURLAuthenticationMethodServerTrust 0
2013-11-02 14:07:07.720 HttpsRequest[485:70b] get the whole response
表明證書確實已經設置完成，現在可以做數據請求了
這裏用的是NSURLConnection的代理方法來執行數據接受，因爲塊方法沒辦法做證書相關的設置
現在看一下請求回來的數據
returnString = [{"id":"52707093fc8712d98a867bcd","title":"八達嶺長城走一走","date":1383177600000,"createUser":{"id":"18638097289","username":"lisi"},"state":"0"},{"id":"52707063fc8712d98a867bcc","title":"雍和宮一日遊","date":1385856000000,"createUser":{"id":"18638097289","username":"lisi"},"state":"0"},{"id":"5270700cfc8712d98a867bca","title":"雍和宮逛一逛","date":1388361600000,"createUser":{"id":"18638097289","username":"lisi"},"state":"0"},{"id":"52707047fc8712d98a867bcb","title":"香山一日遊","date":1388448000000,"createUser":{"id":"18638097289","username":"lisi"},"state":"0"}]
到這裏爲止，https的數據請求證書問題已經得到了解決。要說一下的是很多人會用AFNetwork的第三方，因爲這個框架也是對NSURLConnection的封裝和擴展，github上有對此類問題的細緻說明，可以看看。這裏只解決方向問題，細節問題還有待各位自己研究