你必须使用NSURLConnectionDelegate来允许HTTPS连接iOS8有新的回调。

弃用:

connection:canAuthenticateAgainstProtectionSpace:
connection:didCancelAuthenticationChallenge:
connection:didReceiveAuthenticationChallenge:

相反，你需要声明:

connectionShouldUseCredentialStorage:发送以确定URL加载器是否应该使用凭据存储来验证连接。 connection:willSendRequestForAuthenticationChallenge: -告诉委托连接将发送一个身份验证挑战请求。

使用willSendRequestForAuthenticationChallenge，你可以像使用已弃用的方法一样使用challenge，例如:

// Trusting and not trusting connection to host: Self-signed certificate
[challenge.sender useCredential:[NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust] forAuthenticationChallenge:challenge];
[challenge.sender continueWithoutCredentialForAuthenticationChallenge:challenge];

如果你想继续使用sendSynchronousRequest，我在这个解决方案:

FailCertificateDelegate *fcd=[[FailCertificateDelegate alloc] init];

NSURLConnection *c=[[NSURLConnection alloc] initWithRequest:request delegate:fcd startImmediately:NO];
[c setDelegateQueue:[[NSOperationQueue alloc] init]];
[c start];    
NSData *d=[fcd getData];

你可以在这里看到:Objective-C SSL同步连接

你必须使用NSURLConnectionDelegate来允许HTTPS连接iOS8有新的回调。

弃用:

connection:canAuthenticateAgainstProtectionSpace:
connection:didCancelAuthenticationChallenge:
connection:didReceiveAuthenticationChallenge:

相反，你需要声明:

connectionShouldUseCredentialStorage:发送以确定URL加载器是否应该使用凭据存储来验证连接。 connection:willSendRequestForAuthenticationChallenge: -告诉委托连接将发送一个身份验证挑战请求。

使用willSendRequestForAuthenticationChallenge，你可以像使用已弃用的方法一样使用challenge，例如:

// Trusting and not trusting connection to host: Self-signed certificate
[challenge.sender useCredential:[NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust] forAuthenticationChallenge:challenge];
[challenge.sender continueWithoutCredentialForAuthenticationChallenge:challenge];

To complement the accepted answer, for much better security, you could add your server certificate or your own root CA certificate to keychain( https://stackoverflow.com/a/9941559/1432048), however doing this alone won't make NSURLConnection authenticate your self-signed server automatically. You still need to add the below code to your NSURLConnection delegate, it's copied from Apple sample code AdvancedURLConnections, and you need to add two files(Credentials.h, Credentials.m) from apple sample code to your projects.

- (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])

    OSStatus                err;
    NSURLProtectionSpace *  protectionSpace;
    SecTrustRef             trust;
    SecTrustResultType      trustResult;
    BOOL                    trusted;

    protectionSpace = [challenge protectionSpace];
    assert(protectionSpace != nil);

    trust = [protectionSpace serverTrust];
    assert(trust != NULL);
    err = SecTrustEvaluate(trust, &trustResult);
    trusted = (err == noErr) && ((trustResult == kSecTrustResultProceed) || (trustResult == kSecTrustResultUnspecified));

    // If that fails, apply our certificates as anchors and see if that helps.
    //
    // It's perfectly acceptable to apply all of our certificates to the SecTrust
    // object, and let the SecTrust object sort out the mess.  Of course, this assumes
    // that the user trusts all certificates equally in all situations, which is implicit
    // in our user interface; you could provide a more sophisticated user interface
    // to allow the user to trust certain certificates for certain sites and so on).

    if ( ! trusted ) {
        err = SecTrustSetAnchorCertificates(trust, (CFArrayRef) [Credentials sharedCredentials].certificates);
        if (err == noErr) {
            err = SecTrustEvaluate(trust, &trustResult);
        }
        trusted = (err == noErr) && ((trustResult == kSecTrustResultProceed) || (trustResult == kSecTrustResultUnspecified));
    }
    if(trusted)
        [challenge.sender useCredential:[NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust] forAuthenticationChallenge:challenge];
}

[challenge.sender continueWithoutCredentialForAuthenticationChallenge:challenge];
}

NSURLRequest有一个叫做setAllowsAnyHTTPSCertificate:forHost:的私有方法，它会做你想做的事情。你可以通过一个类别在NSURLRequest上定义allowsAnyHTTPSCertificateForHost:方法，并设置它为你想要覆盖的主机返回YES。

您可以使用此代码

-(void)connection:(NSURLConnection *)connection willSendRequestForAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge
{
     if ([[challenge protectionSpace] authenticationMethod] == NSURLAuthenticationMethodServerTrust)
     {
         [[challenge sender] useCredential:[NSURLCredential credentialForTrust:[[challenge protectionSpace] serverTrust]] forAuthenticationChallenge:challenge];
     }
}

使用-connection:willSendRequestForAuthenticationChallenge:代替这些已弃用的方法

弃用:

-(BOOL)connection:(NSURLConnection *)connection canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace *)protectionSpace  
-(void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge 
-(void)connection:(NSURLConnection *)connection didCancelAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge