1、dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
dispatch_async(dispatch_get_main_queue(), ^{
NSLog(@"%@",self.dict);
});
dispatch_async(dispatch_get_main_queue(), ^{
NSLog(@"%@",self.dict);
});
2、[self performSelectorInBackground:@selector(test) withObject:nil];
3、[self performSelectorOnMainThread:@selector(test1) withObject:nil waitUntilDone:NO];
3.1 waitUntilDone:YES/NO 表示是否要等到test1执行完之后,才执行下面的操作
4、- (void)performSelector:(SEL)aSelector onThread:(NSThread *)thr withObject:(id)arg waitUntilDone:(BOOL)wait;