检查dispatch_queue_t的相等性 [英] checking for equality on dispatch_queue_t

问题描述

如何检查dispatch_queue_t vars之间的相等性？

How can I check for equality between dispatch_queue_t vars?

dispatch_queue_t currentQueue = dispatch_get_current_queue();
dispatch_queue_t mainQueue = dispatch_get_main_queue();
if (currentQueue == mainQueue) {

}

从文档：

typedef struct dispatch_queue_s *dispatch_queue_t;

我不确定，但这是否意味着它是一个指向dispatch_queue_s结构的指针？

I'm not sure but does this mean that it's a pointer to a dispatch_queue_s struct?

由于我不能检查指针的相等性，我不知道如何检查dispatch_queue_t是否与另一个相同？

Since I can't check equality on pointers, I'm not sure how can I check if a dispatch_queue_t is the same as another?

推荐答案

这取决于你所在的队列。在这种特殊情况下使用：

This depends on the queue you're on. In this particular case use:

if ([NSThread isMainThread]) {}

通常，您可以使用 dispatch_get_current_queue（）来测试您的队列。在这种情况下，您可以使用 == 运算符。要引用Apple的并发编程指南中的调度队列页面：

In general, you can use dispatch_get_current_queue() to test which queue your're on. In that case you can use the == operator to do so. To quote the Dispatch Queues page in Apple's Concurrency Programming Guide:

使用dispatch_get_current_queue函数进行调试，或者使用
来测试身份的当前队列。在块对象内从
调用此函数返回块是
提交的队列（并且现在可能正在运行它）。从块外部调用此
函数将为应用程序返回默认并发队列
。

Use the dispatch_get_current_queue function for debugging purposes or to test the identity of the current queue. Calling this function from inside a block object returns the queue to which the block was submitted (and on which it is now presumably running). Calling this function from outside of a block returns the default concurrent queue for your application.

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