如果是单个的webview或者request请求，在请求的文件h中直接实现NSURLConnectionDelegate，并在m中添加下列实现下列两个方法：

C代码  

1. - (BOOL)connection:(NSURLConnection *)connection canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace *)protectionSpace {  
2.     return [protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust];  
3. }  
4.   
5. - (void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge {  
6.     if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust])  
7.         //if ([trustedHosts containsObject:challenge.protectionSpace.host])  
8.             [challenge.sender useCredential:[NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust]   
9.                  forAuthenticationChallenge:challenge];    
10.     [challenge.sender continueWithoutCredentialForAuthenticationChallenge:challenge];  
11. }  

- (BOOL)connection:(NSURLConnection *)connection canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace *)protectionSpace {    return [protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust];}- (void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge {    if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust])        //if ([trustedHosts containsObject:challenge.protectionSpace.host])            [challenge.sender useCredential:[NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust]                  forAuthenticationChallenge:challenge];      [challenge.sender continueWithoutCredentialForAuthenticationChallenge:challenge];}

 上述方法很不爽的是每个请求的地方都要加。

如果项目中用到了three20，直接修改“TTRequestLoader.m”即可，这个文件本身就已经实现了NSURLConnectionDelegate，

修改如下，只改这一个地方就行，处处可用。

C代码  

1. ///////////////////////////////////////////////////////////////////////////////////////////////////  
2. - (void)connection:(NSURLConnection *)connection  
3. didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge{  
4.     //修改  
5.     if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust])  
6.         [challenge.sender useCredential:[NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust] forAuthenticationChallenge:challenge];  
7.     [challenge.sender continueWithoutCredentialForAuthenticationChallenge:challenge];  
8.       
9.     TTDCONDITIONLOG(TTDFLAG_URLREQUEST, @"  RECEIVED AUTH CHALLENGE LOADING %@ ", _urlPath);  
10.     [_queue loader:self didReceiveAuthenticationChallenge:challenge];  
11. }  
12.   
13. //添加  
14. - (BOOL)connection:(NSURLConnection *)connection canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace *)protectionSpace {  
15.     return [protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust];  
16. }  

///////////////////////////////////////////////////////////////////////////////////////////////////- (void)connection:(NSURLConnection *)connectiondidReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge{    //修改    if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust])        [challenge.sender useCredential:[NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust] forAuthenticationChallenge:challenge];    [challenge.sender continueWithoutCredentialForAuthenticationChallenge:challenge];        TTDCONDITIONLOG(TTDFLAG_URLREQUEST, @"  RECEIVED AUTH CHALLENGE LOADING %@ ", _urlPath);    [_queue loader:self didReceiveAuthenticationChallenge:challenge];}//添加- (BOOL)connection:(NSURLConnection *)connection canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace *)protectionSpace {    return [protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust];}

ios项目绕过证书访问https程序