使用 Javascript 中的 setTimeout 函数更改 H1 的文本颜色

4回答

杨__羊羊

感谢所有这些答案，但我自己找到了最简单、最干净的解决方案。只是前一个函数中的 settimeout 函数，以循环方式。它更加漂亮和清晰。下面是代码片段。<body>    <h1 id="first">Text 1</h1>    <h1 id="second">Text 2</h1>    <h1 id="third">Text 3</h1></body><script>first();function first(){document.getElementById('third').style.color="#333";document.getElementById('first').style.color="#32A067";setTimeout(second,10000);}function second(){document.getElementById('first').style.color="#333";document.getElementById('second').style.color="#32A067";setTimeout(third,15000);}function third(){document.getElementById('second').style.color="#333";document.getElementById('first').style.color="#32A067";setTimeout(first,18000);}</script>

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肥皂起泡泡

您必须使用循环数组和超时来睡眠并调用该函数listElements包含所有要突出显示的元素及其突出显示时间startAutoIndex每次调用该函数时都会递增，因此它将首先从元素 id 开始var startAutoIndex = 0function startAuto() {    let listElements = [        {id: "first", timer: 10000},         {id: "second", timer: 13000},         {id: "third", timer: 26000}    ]    function colorHeader(currentIndex) {        for (let index = 0; index < listElements.length; index++) {            const element = listElements[index]            if (currentIndex != index)                document.getElementById(element.id).style.color = '#333'            else {                document.getElementById(element.id).style.color = '#32A067'            }        }    }    let currentIndex =        ((startAutoIndex % listElements.length) + listElements.length) %        listElements.length    colorHeader(currentIndex)    setTimeout(startAuto, listElements[currentIndex].timer)    startAutoIndex = currentIndex + 1}

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喵喵时光机

您可以将主计时器包含在一个间隔内，并将每个突出显示事件作为单独的超时。我还会向您要查询的元素添加一个类，或者只选择所有h1元素。您还可以提供固定超时，它会为您计算元素之间的超时。window.startAuto = () => {  start({    selector : '.highlighter',    timeouts : [ 1000, 2000, 1000 ], // or, for a fixed timout: 1000    callback : (el, index, activeIndex) => {      el.classList.toggle('active', index === activeIndex);    }  });};const defaultOptions = {  selector : '',  timeouts : [],  initialDelay : 0};const start = (options) => {  let opts = Object.assign({}, defaultOptions, options);  opts.elements = Array.from(document.querySelectorAll(opts.selector));  let interval = 0;  if (!Array.isArray(opts.timeouts)) {    opts.timeouts = fillArray(opts.timeouts, opts.elements.length);  }  interval = opts.timeouts.reduce((t, x) => t + x, 0);  opts.timeouts = normalizeTimeouts(opts.timeouts);  setTimeout(() => {    update(opts);    setInterval(update, interval, opts);  }, opts.initialDelay);};const normalizeTimeouts = (timeouts) => {  return timeouts.reduce((results, timeout, index, all) => {    return results.concat(timeout + all.slice(0, index).reduce((t, x) => t + x, 0));  }, [0]);};const update = (opts) => {  opts.timeouts.slice(0, opts.timeouts.length -1).forEach((timeout, index) => {    setTimeout(() => {      opts.elements.forEach((element, i) => {        return opts.callback.call(element, element, i, index);      });    }, timeout);  })};const fillArray = (value, count) => new Array(count).fill(value);.active {  color: green;}<body onload="startAuto()">  <h1 class="highlighter" id="first">Text 1</h1>  <h1 class="highlighter" id="second">Text 2</h1>  <h1 class="highlighter" id="third">Text 3</h1></body>这里有超动态；可重用的类。document.addEventListener('DOMContentLoaded', () => main());const main = () => {  let looper = new Looper({    selector : '.highlighter',    timeouts : [ 1000, 2000, 1000 ], // or, for a fixed timout: 1000    callback : (el, index, activeIndex) => {      el.classList.toggle('active', index === activeIndex);    },    initialDelay : 1000,    autoStart : true  })    document.querySelector('#stop-btn').addEventListener('click', (e) => {    looper.stop();  });    document.querySelector('#restart-btn').addEventListener('click', (e) => {    looper.stop();    looper.start();  });}class Looper {  constructor(options) {    let opts = Object.assign({}, Looper.defaultOptions, options);    this.elements = Array.from(document.querySelectorAll(opts.selector));    if (!Array.isArray(opts.timeouts)) {      opts.timeouts = this.__fillArray(opts.timeouts, this.elements.length);    }    this.interval = opts.timeouts.reduce((t, x) => t + x, 0);    this.timeouts = this.__normalizeTimeouts(opts.timeouts);    this.initialDelay = opts.initialDelay;    this.autoStart = opts.autoStart;    this.callback = opts.callback;    this.__startupId = null;    this.__processId = null;    this.__subprocessIds = this.__fillArray(null, this.elements.length);        if (this.autoStart === true) this.start();  }    start() {    if (this.callback == null) {      throw new Error('callback function is undefined');    }    if (this.__processId == null) {      this.__startupId = setTimeout(() => {        this.__update();        this.__processId = setInterval(() => {          this.__update();        }, this.interval);      }, this.initialDelay);    }  }  stop() {    this.__subprocessIds.forEach((id, index) => {      if (id != null) {        clearTimeout(id);        this.__subprocessIds[index] = null;      }    });    if (this.__processId != null) {      clearInterval(this.__processId);      this.__processId = null;    }    if (this.__startupId != null) {      clearTimeout(this.__startupId);      this.__startupId = null;    }  }  __update() {    let self = this;    self.timeouts.slice(0, this.timeouts.length -1).forEach((timeout, index) => {      self.__subprocessIds[index] = setTimeout(() => {        self.elements.forEach((element, i) => {          return self.callback.call(element, element, i, index);        });      }, timeout);    })  }  __normalizeTimeouts(timeouts) {    return timeouts.reduce((results, timeout, index, all) => {      return results.concat(timeout + all.slice(0, index).reduce((t, x) => t + x, 0));    }, [0]);  }  __fillArray(value, count) {    return new Array(count).fill(value);  }}Looper.defaultOptions = {  selector : '',  timeouts : [],  initialDelay : 0,  autoStart : false}.active {  color: green;}<div>  <h2 class="highlighter" id="first">Text 1</h2>  <h2 class="highlighter" id="second">Text 2</h2>  <h2 class="highlighter" id="third">Text 3</h2></div><button id="stop-btn">Stop</button><button id="restart-btn">Restart</button>

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紫衣仙女

您可以将 setTimeout 与 Promise 一起使用来实现您想要的结果。看看我的片段：var first = document.getElementById('first');    var second = document.getElementById('second');    var third = document.getElementById('third');  const promiseTimeout = (delay, element, newColor) =>    {      return new Promise((resolve, reject) => {        setTimeout(() => {                    element.style.color = newColor;          resolve() // when this fires, .then gets called                  }, delay)      });    }  function start(){    first.style.color = "green";    promiseTimeout(10000, first, "#333")    .then(() => {      return second.style.color = "green";    })    .then(() => {      return promiseTimeout(15000, second, "#333")    })    .then(() => {      third.style.color = "green";      return promiseTimeout(18000, third, "#333")    })    .then(() => start());  }  start();<h1 id="first">Text 1</h1><h1 id="second">Text 2</h1><h1 id="third">Text 3</h1><script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

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