让iOS程序长久在后台运行

#import "AppDelegate.h"
@property (nonatomic, assign) UIBackgroundTaskIdentifier backgroundTask;
- (void)applicationDidEnterBackground:(UIApplication *)application{
    [self startBackgroundUpdateTask];
    /**加入长久运行的代码
    ... ...
    ... ...
    ... ...
    **/
    [self endBackgroundUpdateTask];
}

- (void)startBackgroundUpdateTask{
    self.backgroundTask = [[UIApplication sharedApplication]beginBackgroundTaskWithExpirationHandler:^{
        [self endBackgroundUpdateTask];
    }];
}

- (void)endBackgroundUpdateTask{
    [[UIApplication sharedApplication] endBackgroundTask:self.backgroundTask];
    self.backgroundTask = UIBackgroundTaskInvalid;
}

仅供参考！！！