间断的JSONparsing器失败，为非转义的控制字符

在iPhone应用程序中search某些文本的function。 代码非常简单，我将urlstring传递给twitter api，然后parsing结果。 尽pipeJSONparsing器的一半时间失败，但未转义的控制字符为“0x0”。 下面的代码和完整的错误信息。

- (void)grabData:(NSString *)searchTerm { NSString *urlString = [NSString stringWithFormat:@"http://search.twitter.com/search.json?q=%@&rpp=25",searchTerm]; NSURL *url = [NSURL URLWithString:urlString]; NSLog(@"Created url:%@",url); //Setup and start async download NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url]; NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self]; [connection release]; [request release]; } - (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data { // Store incoming data into a string NSString *jsonString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]; //NSLog(@"Did receive some data %@",jsonString); //Create a dictionary from the JSON string NSDictionary *results = [jsonString JSONValue]; // Build an Array from the dictionary for easy access to each entry NSDictionary *tweets = [results objectForKey:@"results"]; // Loop through each entry in the dictionary for(NSDictionary *tweet in tweets) { // Get the user string for the tweet NSString *tUser = [tweet objectForKey:@"from_user"]; NSLog(@"Tweet from %@",tUser); } } 

来自控制台的错误消息，50％的时间，其他50％按预期工作。

 2010-12-20 21:22:02.022 TwitterSearch[47362:207] Created url:http://search.twitter.com/search.json?q=red&rpp=25 2010-12-20 21:22:02.361 TwitterSearch[47362:207] -JSONValue failed. Error trace is: ( "Error Domain=org.brautaset.JSON.ErrorDomain Code=5 \"Unescaped control character '0x0'\" UserInfo=0x4d6a130 {NSLocalizedDescription=Unescaped control character '0x0'}", "Error Domain=org.brautaset.JSON.ErrorDomain Code=3 \"Object value expected for key: profile_image_url\" UserInfo=0x4d6a200 {NSUnderlyingError=0x4d6a170 \"Unescaped control character '0x0'\", NSLocalizedDescription=Object value expected for key: profile_image_url}", "Error Domain=org.brautaset.JSON.ErrorDomain Code=3 \"Expected value while parsing array\" UserInfo=0x4d6a240 {NSUnderlyingError=0x4d6a1e0 \"Object value expected for key: profile_image_url\", NSLocalizedDescription=Expected value while parsing array}", "Error Domain=org.brautaset.JSON.ErrorDomain Code=3 \"Object value expected for key: results\" UserInfo=0x4d6a310 {NSUnderlyingError=0x4d6a2d0 \"Expected value while parsing array\", NSLocalizedDescription=Object value expected for key: results}" ) 

Answer 1

didReceiveData方法可以在数据交付时多次调用。 所以在这个方法中，你应该简单地将每个传入的块附加到一个NSMutableData类variables（不处理它）。

完整数据的处理应该在connectionDidFinishLoading方法中完成。

这个错误可能是因为它试图parsing一部分数据。