新项目中要求把整个请求参数的json用AES加密生成一个字符串传给服务器，本人网络库用的是AFNetworking，加密后试了一下提示“The ... argument is not valid JSON”, 因为请求参数不是json AFNetworking给自动过滤掉了.查看了AFNetworking的源码，只需要找到

- (NSURLRequest *)requestBySerializingRequest:(NSURLRequest *)request
                               withParameters:(id)parameters
                                        error:(NSError *__autoreleasing *)error
方法，做如下修改就可以了，注释掉的是源码部分，希望能帮助到更多的小伙伴！
#pragma mark - AFURLRequestSerialization
- (NSURLRequest *)requestBySerializingRequest:(NSURLRequest *)request
                               withParameters:(id)parameters
                                        error:(NSError *__autoreleasing *)error
    NSParameterAssert(request);
    if ([self.HTTPMethodsEncodingParametersInURI containsObject:[[request HTTPMethod] uppercaseString]]) {
        return [super requestBySerializingRequest:request withParameters:parameters error:error];
    NSMutableURLRequest *mutableRequest = [request mutableCopy];
    [self.HTTPRequestHeaders enumerateKeysAndObjectsUsingBlock:^(id field, id value, BOOL * __unused stop) {
        if (![request valueForHTTPHeaderField:field]) {
            [mutableRequest setValue:value forHTTPHeaderField:field];
    if (parameters) {
        if (![mutableRequest valueForHTTPHeaderField:@"Content-Type"]) {
            [mutableRequest setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
//        if (![NSJSONSerialization isValidJSONObject:parameters]) {
//            if (error) {
//                NSDictionary *userInfo = @{NSLocalizedFailureReasonErrorKey: NSLocalizedStringFromTable(@"The `parameters` argument is not valid JSON.", @"AFNetworking", nil)};
//                *error = [[NSError alloc] initWithDomain:AFURLRequestSerializationErrorDomain code:NSURLErrorCannotDecodeContentData userInfo:userInfo];
//            }
//            return nil;
//        }
        if ([parameters isKindOfClass:[NSString class]]) {
            [mutableRequest setHTTPBody:[parameters dataUsingEncoding:NSUTF8StringEncoding]];
        }else{
            [mutableRequest setHTTPBody:[NSJSONSerialization dataWithJSONObject:parameters options:self.writingOptions error:error]];
//        NSData *jsonData = [NSJSONSerialization dataWithJSONObject:parameters options:self.writingOptions error:error];
//        if (!jsonData) {
//            return nil;
//        }
//        [mutableRequest setHTTPBody:jsonData];