如何在xcode中调用多个webservice

Question

我想从不同路径的 url 下载 10 个不同的视频，假设我的 url 是 http://someurl/document /path1.mp4 直到path10.mp4。我想通过http连接post方法来做到这一点，是否可能以及如何做。如果我这样做，我需要创建connetion1，连接2......连接10跟踪我在 connectionDidreceive Response 方法中获得响应的（连接）数据。

基本上想要的是一起下载视频，也就是说我不想像下载第一个视频然后第二个然后第三个那样做，但我想要的是开始同时下载所有视频这可能吗？如何？

Answer 1

您可以使用 NSOperationQueue 进行并发下载。 http://www.cimgf.com/2008/ 02/16/cocoa-tutorial-nsoperation-and-nsoperationqueue/ 或查看 ASIHTTPRequest http://allseeing-i.com/ASIHTTPRequest/How-to-use 查找ASINetworkQueue示例：https://gist.github.com/150447

Answer 2

这当然是可能的。

如果您正在寻找一种管理这些多个请求的好方法，而不仅仅是开始并放任它们；我相信这个线程可能会阐明这个问题。它似乎强调了一些管理多个请求的建议，您可能会发现这些建议很有帮助。

Answer 3

1. 如果您有文件 URL，那么您可能不需要 post 方法。当您向服务器发送一些参数时，会专门使用此方法。

2. Well ConnectiondidReceiveResponse 在响应已到达的参数中发送连接对象。

3. 最佳实践是编写一个具有一个连接对象的类，并使用不同的 URL 和文件特定参数（如保存位置等）初始化 10 个这样的类。然后该类将处理下载的所有复杂性。完成后，它可以用文件名通知调用者类。 。

Answer 4

-(void)getMeetings
{
    NSString *requestURL = [NSString stringWithFormat:@"%@",@"someurl"];
    [self webserviceCreate:nil urlOfwebservice:[NSURL URLWithString:requestURL] tag:1];
}

-(void)webserviceCreatePost:(NSDictionary *)dict urlOfwebservice:(NSURL *)url tag:(int)tag
{
    NSError *error = nil;
    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:dict
                                                       options:NSJSONWritingPrettyPrinted
                                                         error:&error];

    NSString *requestJson = @"";
    if (!jsonData) {
        //Deal with error
    } else {
        requestJson = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
    }

    NSLog(@"jsonRequest is %@", requestJson);

    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url
                                                           cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:60.0];
    connectionToInfoMapping = CFDictionaryCreateMutable(kCFAllocatorDefault,0,&kCFTypeDictionaryKeyCallBacks,&kCFTypeDictionaryValueCallBacks);

    NSData *requestData = [requestJson dataUsingEncoding:NSUTF8StringEncoding];

    [request setHTTPMethod:@"POST"];
    [request setValue:@"application/json" forHTTPHeaderField:@"Accept"];
    [request setValue:[[NSUserDefaults standardUserDefaults]valueForKey:@"SessionKey"] forHTTPHeaderField:@"Authorization"];
    [request setValue:[NSString stringWithFormat:@"%d", [requestData length]] forHTTPHeaderField:@"Content-Length"];
    [request setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
    [request setHTTPBody: requestData];

    NSURLConnection *connection = [[NSURLConnection alloc]initWithRequest:request delegate:self];
    CFDictionaryAddValue(connectionToInfoMapping,(__bridge const void *)(connection),
                         (__bridge const void *)([NSMutableDictionary
                                                  dictionaryWithObjectsAndKeys:[NSMutableData data],@"receivedData",[NSString stringWithFormat:@"%d",tag],@"tag", nil]));
}

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
    //    [receivedData setLength:0];
    NSMutableDictionary *connectionInfo = CFDictionaryGetValue(connectionToInfoMapping, (__bridge const void *)(connection));
    receivedData = [connectionInfo objectForKey:@"receivedData"];
    [receivedData setLength:0];

}

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
    NSMutableDictionary *connectionInfo = CFDictionaryGetValue(connectionToInfoMapping, (__bridge const void *)(connection));
    [[connectionInfo objectForKey:@"receivedData"] appendData:data];
}

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
    [HUD hide:YES];
    UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"Error" message:[error localizedDescription] delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
    [alert show];
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    NSMutableDictionary *connectionInfo = CFDictionaryGetValue(connectionToInfoMapping, (__bridge const void *)(connection));

    int tag = [[connectionInfo valueForKey:@"tag"] intValue];

    if (tag == 1)
    {
      NSArray *arrMeeting = [NSJSONSerialization JSONObjectWithData:[connectionInfo valueForKey:@"receivedData"] options:0 error:nil];
}
}