Question

我有两对功能。这些功能需要运行9次，持续3秒（时间长度）。每次运行之间的延迟应为1秒。

有没有更好的方法来缩短loopIT（）函数？

window.onload = function () {

  // Get the button that will trigger the action
  var b = document.getElementById('trigger');
  // and set the onclick handler here instead of in HTML
  b.onclick = loopIT;

  function startIT() {
    // close switch, turn the light on.
  }
  function stopIT() {
    // open switch, turn the light off.
  }

  function loopIT() {
    // Lights on, wait 3 seconds, turn lights off. #1
    setTimeout(startIT, 100);
    setTimeout(stopIT, 3100);
    // Lights on, wait 3 seconds, turn lights off. #2
    setTimeout(startIT, 4100);
    setTimeout(stopIT, 7100);
    // Lights on, wait 3 seconds, turn lights off. #3
    setTimeout(startIT, 8100);
    setTimeout(stopIT, 11100);
    // Lights on, wait 3 seconds, turn lights off. #4
    setTimeout(startIT, 12100);
    setTimeout(stopIT, 15100);
    // Lights on, wait 3 seconds, turn lights off. #4
    setTimeout(startIT, 16100);
    setTimeout(stopIT, 19100);
    // Lights on, wait 3 seconds, turn lights off. #5
    setTimeout(startIT, 22100);
    setTimeout(stopIT, 25100);
    // Lights on, wait 3 seconds, turn lights off. #6
    setTimeout(startIT, 26100);
    setTimeout(stopIT, 29100);
    // Lights on, wait 3 seconds, turn lights off. #7
    setTimeout(startIT, 30100);
    setTimeout(stopIT, 33100);
    // Lights on, wait 3 seconds, turn lights off. #8
    setTimeout(startIT, 34100);
    setTimeout(stopIT, 37100);
    // Lights on, wait 3 seconds, turn lights off. #9
  }        
}

Answer 1

你可以使用两个for循环。

    function loopIT() {
        // goes from #1 to #4 (inclusive)
        for (var i = 4000; i <= 16000; i += 4000) {
            setTimeout(startIT, i + 100);
            setTimeout(stopIT, i + 3100);
        }
        // goes from #5 to #9 (inclusive)
        for (var j = 22000; j <= 34000; j += 4000) {
            setTimeout(startIT, j + 100);
            setTimeout(stopIT, j + 3100);
        }
    }

Answer 2

您可以使用setInterval，它将每N毫秒运行一次某个功能。

您可以使用计数器在N次后停止。

＆＃13;

// count the number of times we turned the lights on
var cpt = 0;
// turn the lights on right away
lightsOn();
// turn the lights on every 3 seconds
var intervalOn = setInterval(lightsOn, 3000);

function lightsOn()
{
  console.log("lights on");

  // Turn the lights off in 1 second
  setTimeout(lightsOff, 1000);
}

function lightsOff()
{
  console.log("lights off");
  ++cpt;
  
  // If we've turned off the lights 9 times, stop turning the lights on.
  if (cpt == 9)
  {
    clearInterval(intervalOn);
  }
}

＆＃13;

Answer 3

我建议使用do-while循环，直到你到达终点（在你的情况下大约40s）。您还可以添加每个循环增加一次的迭代器。

function loopIt() {

  let timeout = 100;

  do {
     setTimeout(startIt(), timeout);
     timeout += 3000;
     setTimeout(stopIt(), timeout);
     timeout += 1000;
  } while (timeout < 40000);

}

Answer 4

我的建议是：

var repeatedTimes = 0;
function loopIt(){ 
    if(repeatedTimes < 9){
      startIT();
      setTimeout(stopIT, 3000);
      setTimeout(loopIt, 4000);
    }
    repeatedTimes++;
}
setTimeout(loopIt, 100);

希望有所帮助

每次运行后如何使2次函数循环延时n次？

4 个答案: