2018-05-25

记录一下GCD网络请求的并发

 // 创建信号量
 dispatch_semaphore_t semaphore = dispatch_semaphore_create(0);
 // 创建全局并行
  dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
  dispatch_group_t group = dispatch_group_create();
  dispatch_group_async(group, queue, ^{

    // 请求一
    [loginCode getUserInfoWithNick:nil andUserId:kUserId onSuc:^(id data) {
        NSLog(@"yue");
        dispatch_semaphore_signal(semaphore);

    } andFail:^(NSError *error) {       
    }];

});
dispatch_group_async(group, queue, ^{

    // 请求二
    [CommodityViewModel getPriceTransformForIntegral:nil onSuccess:^(id data) {

        NSLog(@"duihuan11");
        dispatch_semaphore_signal(semaphore);

    } onFailure:^(NSError *error) {
    }];
});
dispatch_group_async(group, queue, ^{

    // 请求三
    [CommodityViewModel getPriceTransformForIntegral:nil onSuccess:^(id data) {
        NSLog(@"duihuan22");
        dispatch_semaphore_signal(semaphore);

    } onFailure:^(NSError *error) {            
    }];
});

dispatch_group_notify(group, queue, ^{

    // 三个请求对应三次信号等待
    dispatch_semaphore_wait(semaphore, DISPATCH_TIME_FOREVER);
    dispatch_semaphore_wait(semaphore, DISPATCH_TIME_FOREVER);
    dispatch_semaphore_wait(semaphore, DISPATCH_TIME_FOREVER);

    //在这里 进行请求后的方法，回到主线程
    dispatch_async(dispatch_get_main_queue(), ^{

        //更新UI操作

    });


});