1、错误一：Error Domain=NSURLErrorDomain Code=-999 "cancelled"
这种报错是因为没有进行HTTPS证书验证，AFNetworking提供了验证证书的方法：
+ (AFSecurityPolicy*)customSecurityPolicy
{
NSString *cerPath = [[NSBundle mainBundle] pathForResource:@"xxx" ofType:@"cer"];//证书的路径
NSData *certData = [NSData dataWithContentsOfFile:cerPath];
AFSecurityPolicy *securityPolicy = [AFSecurityPolicy policyWithPinningMode:AFSSLPinningModeCertificate];
securityPolicy.allowInvalidCertificates = YES;
securityPolicy.validatesDomainName = NO;
securityPolicy.pinnedCertificates = @[certData];
return securityPolicy;
}2、错误二：报400或者415
这种是需要将请求参数设为JSON格式
AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];
manager.requestSerializer = [AFJSONRequestSerializer serializer];