多线程
//后台执行 dispatch_async(dispatch_get_global_queue(0, 0), ^{ //something }); //主线程执行 dispatch_async(dispatch_get_main_queue(),^{ //something }); //一次性执行 static dispatch_once_t onceToken; dispatch_once(&onceToken,^{ // code to be executed once }); //延迟2秒执行 double delayInSeconds = 2.0; dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW,delayInSeconds * NSEC_PER_SEC);
dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
//code to be executed on the main queue after delay }); //自定义dispatch_queue_t dispatch_queue_t urls_queue = dispatch_queue_create("blog.devtang.com", NULL); dispatch_async(urls_queue, ^{ //yuro code }); dispatch_release(urls_queue); //合并汇总结果 dispatch_group_t group = dispatch_group_create(); dispatch_group_async(group, dispatch_get_global_queue(0, 0), ^{ //并行执行的线程一 }); dispatch_group_async(group, dispatch_get_global_queue(0, 0), ^{ //并行执行的线程二 }); dispatch_group_notify(group, dispatch_get_global_queue(0, 0), ^{ //汇总结果 });