在 Objective-c 中使用 Post 方法获取数据

Question

我正在使用 POST 方法获取数据。我已经成功检索到所有数据。在 UI 中显示它需要很长时间，但我可以立即在控制台上打印它，我的代码是

NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:[NSURL URLWithString:@"http://www.xxxyyy.com/v1/api/client/authorize"]];
[request setHTTPMethod:@"POST"];
[request setValue:@"ABCD" forHTTPHeaderField:@"Authkey"];
[request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];

 NSURLSession *session = [NSURLSession sessionWithConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration]];

[[session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) 
{
    NSString *requestReply = [[NSString alloc] initWithData:data encoding:NSASCIIStringEncoding];

    [request setValue:@"application/json;charset=UTF-8" forHTTPHeaderField:@"Authkey"];

    NSData* data1 = [requestReply dataUsingEncoding:NSUTF8StringEncoding];
    jsonReturnArray = [NSJSONSerialization JSONObjectWithData:data1 options:NSJSONReadingAllowFragments error:&error];

    NSArray *array = [jsonReturnArray copy];
    [self rec:array];

    NSString *phoneNumber=[NSString stringWithFormat:@"%@",[jsonReturnArray valueForKey:@"phone"]];
    lblPhoneNumber.text = phoneNumber;

    NSString *Address=[NSString stringWithFormat:@"%@ %@ %@,CA %@",[jsonReturnArray valueForKey:@"street1"],[jsonReturnArray valueForKey:@"street2"],[jsonReturnArray valueForKey:@"city"],[jsonReturnArray valueForKey:@"postalcode"]];
    lblAddress.text=Address;//takes long time to display
    NSLog(@"%@",Address);//immeaditely print

    strlatitude=[jsonReturnArray valueForKey:@"latitude"];
    strlongitude=[jsonReturnArray valueForKey:@"longitude"];

    [self Map:(MKMapView *)mapLocation didUpdateUserLocation:(MKUserLocation *)nil];//method call
}] resume];

Answer 1

这太花时间来打印数据，但如果你使用 NSURLConnection 类，它可能会对你有所帮助。这是我的 Class 方法，它可能会有所帮助。

+ (void)postRequestData:(NSDictionary *)postVars
                 Action:(APIMode)action
  WithCompletionHandlar:(void (^) (id result, BOOL status))completionBlock
{

    NSURL *url = [NSURL URLWithString:API_URL([self getAPINameForType:action])];
    NSLog(@"Request URL %@",[NSString stringWithFormat:@"%@",url]);
    NSString *contentType = @"application/json";
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
    [request setHTTPMethod:@"POST"];
    [request addValue:contentType forHTTPHeaderField: @"Content-Type"];
    NSError *err = nil;

    NSMutableDictionary *params=[[NSMutableDictionary alloc] initWithDictionary:postVars];
    //  [params setObject:[self getAPINameForType:action] forKey:@"mode"];
    NSLog(@"Paramater %@",params);

    NSData *body = [NSJSONSerialization dataWithJSONObject:params options:NSJSONWritingPrettyPrinted error:&err];
    [request setHTTPBody:body];
    [request addValue:[NSString stringWithFormat:@"%lu", (unsigned long)body.length] forHTTPHeaderField: @"Content-Length"];

    [NSURLConnection sendAsynchronousRequest:request
                                       queue:[NSOperationQueue mainQueue]
                           completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError)
     {
         if(!connectionError)
         {
             NSError *error = nil;

             NSDictionary *dictResponse = [NSDictionary dictionaryWithDictionary:[NSJSONSerialization JSONObjectWithData:data
                                                                                                                 options:NSJSONReadingAllowFragments error:&error]];

             dispatch_async(dispatch_get_main_queue(), ^{
                 completionBlock(dictResponse,(error == nil));
             });

             NSLog(@"%@",dictResponse);
         }
         else
         {
             dispatch_async(dispatch_get_main_queue(), ^{
                 completionBlock(connectionError.localizedDescription,NO);
             });
         }
     }];
}

使用这个方法代替它。它执行得很快，因为 NSURLConnection 类在后台执行。

Answer 2

尝试使用 NSURLConnection 类（手动代码）或简单地使用 AFNetworking 类（更少代码）来获取您的数据。 AFNetworking 内部使用 NSURLConnection 类本身。