Question

我似乎无法获得以下代码来阻止无限循环。我对JS很新，在codepen上发现了这个。它对我正在进行的项目非常有用，但前提是我可以让它无限期地停止循环。在键入最后一个短语后停止它将是理想的。想法？

    <style>
    body {
        background-color:#333;
        text-align: center;
    }
    * { color:#fff; text-decoration: none;}
</style>
<script>
    var TxtType = function(el, toRotate, period) {
        this.toRotate = toRotate;
        this.el = el;
        this.loopNum = 0;
        this.period = parseInt(period, 10) || 2000;
        this.txt = '';
        this.tick();
        this.isDeleting = false;
    };

    TxtType.prototype.tick = function() {
        var i = this.loopNum % this.toRotate.length;
        var fullTxt = this.toRotate[i];

        if (this.isDeleting) {
            this.txt = fullTxt.substring(0, this.txt.length - 1);
        } else {
            this.txt = fullTxt.substring(0, this.txt.length + 1);
        }

        this.el.innerHTML = '<span class="wrap">'+this.txt+'</span>';

        var that = this;
        var delta = 200 - Math.random() * 100;

        if (this.isDeleting) { delta /= 2; }

        if (!this.isDeleting && this.txt === fullTxt) {
            delta = this.period;
            this.isDeleting = true;
        } else if (this.isDeleting && this.txt === '') {
            this.isDeleting = false;
            this.loopNum++;
            delta = 500;
        }

        setTimeout(function() {
            that.tick();
        }, delta);
    };

    window.onload = function() {
        var elements = document.getElementsByClassName('typewrite');
        for (var i=0; i<elements.length; i++) {
            var toRotate = elements[i].getAttribute('data-type');
            var period = elements[i].getAttribute('data-period');
            if (toRotate) {
                new TxtType(elements[i], JSON.parse(toRotate), period);
            }
        }
        // INJECT CSS
        var css = document.createElement("style");
        css.type = "text/css";
        css.innerHTML = ".typewrite > .wrap { border-right: 0.08em solid #fff}";
        document.body.appendChild(css);
    };
</script>

    <h1>
    <a href="" class="typewrite" data-period="2000" data-type='[ "Discover", "Learn", "Train", "Prepare", "Share" ]'>
        <span class="wrap"></span>
    </a>
</h1>

Answer 1

你可以在最后一个元素之后通过检查loopNum是否仍然小于单词数组的长度来停止它。

if(this.loopNum < this.toRotate.length){
    setTimeout(function() {
        that.tick();
    }, delta);
}

＆＃13;

<style>
    body {
        background-color:#333;
        text-align: center;
    }
    * { color:#fff; text-decoration: none;}
</style>
<script>
    var TxtType = function(el, toRotate, period) {
        this.toRotate = toRotate;
        this.el = el;
        this.loopNum = 0;
        this.period = parseInt(period, 10) || 2000;
        this.txt = '';
        this.tick();
        this.isDeleting = false;
    };

    TxtType.prototype.tick = function() {
        var i = this.loopNum % this.toRotate.length;
        var fullTxt = this.toRotate[i];

        if (this.isDeleting) {
            this.txt = fullTxt.substring(0, this.txt.length - 1);
        } else {
            this.txt = fullTxt.substring(0, this.txt.length + 1);
        }

        this.el.innerHTML = '<span class="wrap">'+this.txt+'</span>';

        var that = this;
        var delta = 200 - Math.random() * 100;

        if (this.isDeleting) { delta /= 2; }

        if (!this.isDeleting && this.txt === fullTxt) {
            delta = this.period;
            this.isDeleting = true;
        } else if (this.isDeleting && this.txt === '') {
            this.isDeleting = false;
            this.loopNum++;
            delta = 500;
        }
        
        if(this.loopNum < this.toRotate.length){
          setTimeout(function() {
              that.tick();
          }, delta);
        }
    };

    window.onload = function() {
        var elements = document.getElementsByClassName('typewrite');
        for (var i=0; i<elements.length; i++) {
            var toRotate = elements[i].getAttribute('data-type');
            var period = elements[i].getAttribute('data-period');
            if (toRotate) {
                new TxtType(elements[i], JSON.parse(toRotate), period);
            }
        }
        // INJECT CSS
        var css = document.createElement("style");
        css.type = "text/css";
        css.innerHTML = ".typewrite > .wrap { border-right: 0.08em solid #fff}";
        document.body.appendChild(css);
    };
</script>

    <h1>
    <a href="" class="typewrite" data-period="2000" data-type='[ "Discover", "Learn", "Train", "Prepare", "Share" ]'>
        <span class="wrap"></span>
    </a>
</h1>

＆＃13;

Answer 2

您可以在打印完最后一个字符串后直接停止循环，在方向更改的检查处。

if (!this.isDeleting && this.txt === fullTxt) {
    delta = this.period;
    this.isDeleting = true;
    if (this.loopNum + 1 === this.toRotate.length) { // add this to stop
        return;
    }

＆＃13;

var TxtType = function(el, toRotate, period) {
  this.toRotate = toRotate;
  this.el = el;
  this.loopNum = 0;
  this.period = parseInt(period, 10) || 2000;
  this.txt = '';
  this.tick();
  this.isDeleting = false;
};

TxtType.prototype.tick = function() {
  var i = this.loopNum % this.toRotate.length;
  var fullTxt = this.toRotate[i];

  if (this.isDeleting) {
    this.txt = fullTxt.substring(0, this.txt.length - 1);
  } else {
    this.txt = fullTxt.substring(0, this.txt.length + 1);
  }

  this.el.innerHTML = '<span class="wrap">' + this.txt + '</span>';

  var that = this;
  var delta = 200 - Math.random() * 100;

  if (this.isDeleting) {
    delta /= 2;
  }

  if (!this.isDeleting && this.txt === fullTxt) {
    delta = this.period;
    this.isDeleting = true;
    if (this.loopNum + 1 === this.toRotate.length) { // add this to stop
      return;
    }
  } else if (this.isDeleting && this.txt === '') {
    this.isDeleting = false;
    this.loopNum++;
    delta = 500;
  }

  setTimeout(function() {
    that.tick();
  }, delta);
};

window.onload = function() {
  var elements = document.getElementsByClassName('typewrite');
  for (var i = 0; i < elements.length; i++) {
    var toRotate = elements[i].getAttribute('data-type');
    var period = elements[i].getAttribute('data-period');
    if (toRotate) {
      new TxtType(elements[i], JSON.parse(toRotate), period);
    }
  }
  // INJECT CSS
  var css = document.createElement("style");
  css.type = "text/css";
  css.innerHTML = ".typewrite > .wrap { border-right: 0.08em solid #fff}";
  document.body.appendChild(css);
};

＆＃13;

body { background-color: #333; text-align: center; }
* { color: #fff; text-decoration: none; }

＆＃13;

<h1>
  <a href="" class="typewrite" data-period="2000" data-type='["Discover", "Learn", "Train", "Prepare", "Share"]'>
    <span class="wrap"></span>
  </a>
</h1>

＆＃13;

停止Inifinite Javascript循环

2 个答案: