Geovani Assis

The “Typewrite” effect or “typewriter effect” is an interesting technique that can be applied to web pages to give a retro touch or emphasize the content. This effect simulates the animation of an old typewriter, revealing text gradually, as if it were being typed in real time.

To achieve this, we will use the following codes:

HTML

<h3 class="typewrite" data-period="2000" data-type='[ "Teste de Efeito Typewrite.", "Efeito Typewrite.", "Efeito Typewrite testando..." ]'><span class="wrap"></span></h3>

JavaScript

    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);
    };

Or you can download the finished file.