怎么忽略HTTPS的证书错误

在AFNetworking中，当服务器证书等有问题的时候，就会导致HTTPS连接发生失败。
如何避免这个，需要OC

AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];

AFSecurityPolicy *securityPolicy = [AFSecurityPolicy policyWithPinningMode:AFSSLPinningModeNone];
securityPolicy.allowInvalidCertificates = YES;
manager.securityPolicy = securityPolicy;

[manager POST:url parameters:nil success:^(AFHTTPRequestOperation *operation, id responseObject)
{
NSLog(@"Response: %@",responseObject);
}
failure:^(AFHTTPRequestOperation *operation, NSError *error)
{
NSLog(@"Error: %@", error);
}];