iOS GCD基本使用（二）

//异步函数+并发队列会开启多条线程，异步执行

- (void)asyncConcurrent{

//1.创建队列

//第一个参数:c语言字符串，就是一个标识符，用来区分队列

//第二个参数：队列的类型：DISPATCH_QUEUE_SERIAL串行DISPATCH_QUEUE_CONCURRENT并行

dispatch_queue_tqueue =dispatch_queue_create("first",DISPATCH_QUEUE_CONCURRENT);

//2.封装任务->添加任务到队列中

//第一个参数：队列

//第二参数：要执行的任务

dispatch_async(queue, ^{

NSLog(@"first====%@",[NSThreadcurrentThread]);

});

dispatch_async(queue, ^{

NSLog(@"second====%@",[NSThreadcurrentThread]);

});

dispatch_async(queue, ^{

NSLog(@"third====%@",[NSThreadcurrentThread]);

});

}

//异步函数+串行队列:会开线程,开一条线程,队列中的任务是串行执行的

-(void)asyncSerial

{

//1.创建队列

dispatch_queue_tqueue =dispatch_queue_create("download",DISPATCH_QUEUE_SERIAL);

//2.封装操作

dispatch_async(queue, ^{

NSLog(@"download1----%@",[NSThreadcurrentThread]);

});

dispatch_async(queue, ^{

NSLog(@"download2----%@",[NSThreadcurrentThread]);

});

dispatch_async(queue, ^{

NSLog(@"download3----%@",[NSThreadcurrentThread]);

});

}

//同步函数+并发队列:不会开线程,任务是串行执行的

-(void)syncConcurrent

{

//1.创建队列

dispatch_queue_tqueue =dispatch_queue_create("download",DISPATCH_QUEUE_CONCURRENT);

NSLog(@"---start---");

//2.封装任务

dispatch_sync(queue, ^{

NSLog(@"download1----%@",[NSThreadcurrentThread]);

});

dispatch_sync(queue, ^{

NSLog(@"download2----%@",[NSThreadcurrentThread]);

});

dispatch_sync(queue, ^{

NSLog(@"download3----%@",[NSThreadcurrentThread]);

});

NSLog(@"---end---");

}

//同步函数+串行队列:不会开线程,任务是串行执行的

-(void)syncSerial

{

//1.创建队列

dispatch_queue_tqueue =dispatch_queue_create("download",DISPATCH_QUEUE_SERIAL);

//2.封装任务

dispatch_sync(queue, ^{

NSLog(@"download1----%@",[NSThreadcurrentThread]);

});dispatch_sync(queue, ^{

NSLog(@"download2----%@",[NSThreadcurrentThread]);

});

dispatch_sync(queue, ^{

NSLog(@"download3----%@",[NSThreadcurrentThread]);

});

//获得全局并发队列

/*

第一个参数:优先级

第二个参数:

*/

dispatch_queue_tqueue =dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,0);