iOS NSURLSessionのピット(The data couldn’t be read because it isn’t in the correct format)
4141 ワード
概要
#pragma mark -
- (void)test{
NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
NSURLSession *session = [NSURLSession sessionWithConfiguration:configuration delegate:delegateObject delegateQueue:[NSOperationQueue mainQueue]];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:@"api.com"];
request.HTTPBody = para//
NSURLSessionTask *task = [session dataTaskWithRequest:request];
[task resume];
}
#pragma mark - NSURLSessionDelegate method
-(void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveResponse:(NSURLResponse *)response completionHandler:(void (^)(NSURLSessionResponseDisposition))completionHandler
{
DeLog(@"1。 %s",__FUNCTION__);
completionHandler(NSURLSessionResponseAllow);
}
-(void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveData:(NSData *)data
{
NSError *error;
NSDictionary *dict = [NSJSONSerialization JSONObjectWithData:self.recevieData options:NSJSONReadingMutableLeaves error:&error];
if (error)
{
NSLog(@"initSDK error === %@",error.localizedDescription);
}
}
-(void)URLSession:(NSURLSession *)session didBecomeInvalidWithError:(NSError *)error{
}
- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(nullable NSError *)error
{
[session finishTasksAndInvalidate];
}
印刷結果:
initSDK error === The data couldn’t be read because it isn’t in the correct formatぶんせき
-(void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveData:(NSData *)dataのdataは完全なデータではない場合がある.[NSByteCountFormatter stringFromByteCount:data countStyle:NSByteCountFormatterCountStyleFile]印刷、完全data=2KB、エラーdata=1KB.data=2KB/data=1KBはランダムに現れる.dataは実はjsonで、それぞれdataをNSDictionaryとNSStringに変えて、NSDictionary=nilで、NSStringは値がありますが、完全なjsonの一部data=1KBのとき、-(void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveData:(NSData *)dataは実際に2回呼び出されます.私は前後2回のdataをつなぎ合わせて、ちょうど完全なjsonです.一方、data=2KBの場合、解決する
-(void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveData:(NSData *)data得られるdataは必ずしも最終的なdataではなく、複数回呼び出される可能性がある以上、純粋で完全なjsonを得るためには、NSURLSessionDelegateの多くの方法の中で呼び出さなければならない.また、要求プロセス全体が完了した後、最後に呼び出される方法であり、この方法はまだ1回しか呼び出されない.- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(nullable NSError *)errorはこの問題を完璧に解決した.通常、sessionを放出するので、この方法にも含まれます.#pragma mark - NSURLSessionDelegate method
#pragma mark - ， data
NSMutableData *_data;
-(void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveData:(NSData *)data
{
if(_data)
{
_data = [[NSMutableData alloc] init];
}
[_data appendData:data];
}
- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(nullable NSError *)error
{
#pragma _data, json
NSDictionary *dict = [NSJSONSerialization JSONObjectWithData:_data options:NSJSONReadingMutableLeaves error:&error];
[session finishTasksAndInvalidate];
}
data=1KBが発生しない場合