ios - 如果app在终止过程中发送http请求，服务器会收到吗？

Question

我想知道如果我的 iOS 应用正在终止，如果我发送一个 HTTP 请求通知服务器用户将要离线，服务器会收到这个请求吗？

我的代码如下:

- (void)applicationWillTerminate:(UIApplication *)application {
    // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
    NSMutableDictionary *para = [[NSMutableDictionary alloc]initWithCapacity:0];
    [para setObject:[[NSUserDefaults standardUserDefaults] valueForKey:@"UserBindId"] forKey:@"unionId"];
    [para setObject:@(0) forKey:@"OnlineState"];
    [Post updateOnlineWithParameters:para withBlock:^(NSDictionary *commitResult, NSError *error) {
        NSLog(@"applicationWillTerminate = %@", commitResult);
    }];
}

Answer 1

参见 Executing Finite-Length Tasks例如，当应用程序进入后台模式时，如何让应用程序请求一点额外时间(最多 3 分钟，这应该足以满足您的目的)。

- (void)applicationDidEnterBackground:(UIApplication *)application
{
    bgTask = [application beginBackgroundTaskWithName:@"GoingOffline" expirationHandler:^{
        // Well, we ran out of time before network request finished ... handle that however you want

        // but tell the OS that we understand, and that the background task is done

        [application endBackgroundTask:bgTask];
        bgTask = UIBackgroundTaskInvalid;
    }];

    NSDictionary *para = @{@"unionID"     : [[NSUserDefaults standardUserDefaults] valueForKey:@"UserBindId"],
                           @"OnlineState" : @0};

    [Post updateOnlineWithParameters:para withBlock:^(NSDictionary *commitResult, NSError *error) {
        // when done, tell the OS that the background task is done

        [application endBackgroundTask:bgTask];
        bgTask = UIBackgroundTaskInvalid;
    }];
}

我试着稍微简化你的参数(不需要可变字典......你可以使用字典文字)，所以根据你的需要进行调整。但希望你能遵循这里的基本思想，如果你想在应用程序进入后台时做一些事情，你必须为此请求权限。