AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
//申明返回的结果是json类型
manager.responseSerializer = [AFJSONResponseSerializer serializer];
//申明请求的数据是json类型
manager.requestSerializer=[AFJSONRequestSerializer serializer];
//如果报接受类型不一致请替换一致text/html或别的
manager.responseSerializer.acceptableContentTypes = [NSSet setWithObject:@"text/html"];
//传入的参数
NSDictionary *parameters = @{@"1":@"XXXX",@"2":@"XXXX",@"3":@"XXXXX"};
//你的接口地址
NSString *url=@"http://xxxxx";
//发送请求
[manager POST:url parameters:parameters success:^(AFHTTPRequestOperation *operation, id responseObject) {
    NSLog(@"JSON: %@", responseObject);
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
    NSLog(@"Error: %@", error);
}];