本文实例为大家分享了js实现数字变动效果展示的具体代码，供大家参考，具体内容如下
$.fn.countTo = function (options) { options = options || {};//当options未被初始化，即typeof options = 'undefined'时，执行后面部分即var options = {}来初始化一个对象 return $(this).each(function () { // set options for current element var settings = $.extend({}, $.fn.countTo.defaults, { from: $(this).data('from'), to: $(this).data('to'), speed: $(this).data('speed'), refreshInterval: $(this).data('refresh-interval'), decimals: $(this).data('decimals') }, options); // how many times to update the value, and how much to increment the value on each update //更新值多少次，每次更新值多快 var loops = Math.ceil(settings.speed / settings.refreshInterval), increment = (settings.to - settings.from) / loops; // references & variables that will change with each update //引用和变量每次更新将改变 var self = this,//返回html对象 $self = $(this),//返回返回一个jquery对象 loopCount = 0, value = settings.from, data = $self.data('countTo') || {};//获取jauery方法对象 $self.data('countTo', data);//赋值 // if an existing interval can be found, clear it first //如果存在间隔，则清除它 if (data.interval) { clearInterval(data.interval); } data.interval = setInterval(updateTimer, settings.refreshInterval); // initialize the element with the starting value //用开始的值初始化 render(value); function updateTimer() { value += increment; loopCount++; render(value); if (typeof(settings.onUpdate) == 'function') { settings.onUpdate.call(self, value); } if (loopCount >= loops) { // remove the interval $self.removeData('countTo'); clearInterval(data.interval); value = settings.to; if (typeof(settings.onComplete) == 'function') { settings.onComplete.call(self, value); } } } function render(value) { var formattedValue = settings.formatter.call(self, value, settings); $self.html(formattedValue); } }); }; $.fn.countTo.defaults = { from: 200, // the number the element should start at to: 0, // the number the element should end at speed: 1000, // how long it should take to count between the target numbers refreshInterval: 1, // how often the element should be updated decimals: 0, // the number of decimal places to show formatter: formatter, // handler for formatting the value before rendering onUpdate: null, // callback method for every time the element is updated onComplete: null // callback method for when the element finishes updating }; function formatter(value, settings) { return value.toFixed(settings.decimals); } // custom formatting example $('#count-number').data('countToOptions', { formatter: function (value, options) { return value.toFixed(options.decimals).replace(/\B(?=(?:\d{3})+(?!\d))/g, ','); } }); // start all the timers $('.timer').each(count); function count(options) { var $this = $(this); options = $.extend({}, options || {}, $this.data('countToOptions') || {}); $this.countTo(options); }apply与call的简单用法，学习链接。
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。
