在IOS中如何通过gcd延迟调用方法？

Question

有没有为什么在调度后用2秒调用方法，就像performSelector：withObject：afterDelay：？

Answer 1

是的，你可以，

Swift 3，Swift 4

DispatchQueue.main.asyncAfter(deadline: .now() + 2.0) {
    <# YOUR CODE HERE #>
}

Swift 2

dispatch_after(dispatch_time(DISPATCH_TIME_NOW, Int64(2.0 * Double(NSEC_PER_SEC))), dispatch_get_main_queue()) { () -> Void in
        <# YOUR CODE HERE #>
}

目标C

dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, 2 * NSEC_PER_SEC);
    dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
        <# YOUR CODE HERE #>
    });

Answer 2

是的，我们可以使用以下代码添加延迟来执行GCD

dispatch_after(dispatch_time(DISPATCH_TIME_NOW, 10 * NSEC_PER_SEC), dispatch_get_main_queue(), ^{
 // Do you work over here
});

希望这会对你有所帮助。

Answer 3

dispatch_time_t deferTime = 2.0f;
dispatch_after(deferTime, dispatch_get_main_queue(), ^{
//call you method here
});