这里是我的2美分= 5个方法;)

我喜欢封装这些细节，让AppCode告诉我如何完成我的句子。

void dispatch_after_delay(float delayInSeconds, dispatch_queue_t queue, dispatch_block_t block) {
    dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, delayInSeconds * NSEC_PER_SEC);
    dispatch_after(popTime, queue, block);
}

void dispatch_after_delay_on_main_queue(float delayInSeconds, dispatch_block_t block) {
    dispatch_queue_t queue = dispatch_get_main_queue();
    dispatch_after_delay(delayInSeconds, queue, block);
}

void dispatch_async_on_high_priority_queue(dispatch_block_t block) {
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), block);
}

void dispatch_async_on_background_queue(dispatch_block_t block) {
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0), block);
}

void dispatch_async_on_main_queue(dispatch_block_t block) {
    dispatch_async(dispatch_get_main_queue(), block);
}

对于Swift，我已经创建了一个全局函数，没什么特别的，使用dispatch_after方法。我更喜欢这个，因为它易于阅读和使用:

func performBlock(block:() -> Void, afterDelay delay:NSTimeInterval){
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, Int64(delay * Double(NSEC_PER_SEC))), dispatch_get_main_queue(), block)
}

你可以这样使用:

performBlock({ () -> Void in
    // Perform actions
}, afterDelay: 0.3)

我认为您正在寻找dispatch_after()。它要求你的块不接受参数，但是你可以让块从你的局部作用域捕获这些变量。

int parameter1 = 12;
float parameter2 = 144.1;

// Delay execution of my block for 10 seconds.
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, 10 * NSEC_PER_SEC), dispatch_get_main_queue(), ^{
    NSLog(@"parameter1: %d parameter2: %f", parameter1, parameter2);
});

更多:https://developer.apple.com/documentation/dispatch/1452876-dispatch_after

这里是我的2美分= 5个方法;)

我喜欢封装这些细节，让AppCode告诉我如何完成我的句子。

void dispatch_after_delay(float delayInSeconds, dispatch_queue_t queue, dispatch_block_t block) {
    dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, delayInSeconds * NSEC_PER_SEC);
    dispatch_after(popTime, queue, block);
}

void dispatch_after_delay_on_main_queue(float delayInSeconds, dispatch_block_t block) {
    dispatch_queue_t queue = dispatch_get_main_queue();
    dispatch_after_delay(delayInSeconds, queue, block);
}

void dispatch_async_on_high_priority_queue(dispatch_block_t block) {
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), block);
}

void dispatch_async_on_background_queue(dispatch_block_t block) {
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0), block);
}

void dispatch_async_on_main_queue(dispatch_block_t block) {
    dispatch_async(dispatch_get_main_queue(), block);
}

按Cmd + Shift + L显示Xcode内置代码片段库:

寻找分派之后，然后，只需拖放到您的代码。

在swift 3中，我们可以简单地使用DispatchQueue.main.asyncAfter函数在延迟'n'秒后触发任何函数或动作。在代码中，我们将延迟设置为1秒后。在此函数体中调用将在延迟1秒后触发的任何函数。

let when = DispatchTime.now() + 1
DispatchQueue.main.asyncAfter(deadline: when) {

    // Trigger the function/action after the delay of 1Sec

}