jQuery动画函数模拟
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>Document</title> <style> div { width: 100px; height: 100px; background-color: pink; position: relative; top: 0; left: 0; padding-left: 10px; } </style> </head> <body> <div></div> <script> /* *@para0 DOM对象 *@para1 目标对象JSON类型 *@para2 动画总时长 *@para3 动画缓冲描述词 *@para4 回调函数 */ function animate(elem, targetJSON, time, tweenString, callback) { if (arguments.length == 3) { tweenString = 'Linear'; callback = null } else if (arguments.length == 4) { switch (typeof arguments[3]) { case 'string': callback = null; break; case 'function': callback = arguments[3]; tweenString = 'Linear' break; default: throw new Error("抱歉,第4个参数要么是缓冲描述词,要么是回调函数,请检查!"); } } // 定义动画每帧间隔时间 var interval = 10; // 定义节流阀 var isanimated = true // 获取DOM对象当前值 var originJSON = {}; // 获取变化量 var changeJSON = {}; for (var k in targetJSON) { targetJSON[k] = parseFloat(targetJSON[k]) originJSON[k] = parseFloat(fetchComputedStyle(elem, k)) changeJSON[k] = targetJSON[k] - originJSON[k] } // 计算总帧率与当前帧率 var allFrame = time / interval var frameCount = 0; // 计算后的步值 var state // 声明定时器 var timer = setInterval(function() { frameCount++ // 利用缓动公式计算步值 for (var k in targetJSON) { state = Tween[tweenString](frameCount, originJSON[k], changeJSON[k], allFrame) if (k != 'opacity') { elem.style[k] = state + 'px'; } else { elem.style[k] = state } } // 当动画完成后停表 if (frameCount >= allFrame) { for (var k in targetJSON) { if (k != 'opacity') { elem.style[k] = targetJSON[k] + 'px' } else { elem.style[k] = targetJSON[k] } } clearInterval(timer); isanimated = false; callback && callback.call(elem) } }, interval) var Tween = { Linear: function(t, b, c, d) { return c * t / d + b; }, //二次的 QuadEaseIn: function(t, b, c, d) { return c * (t /= d) * t + b; }, QuadEaseOut: function(t, b, c, d) { return -c * (t /= d) * (t - 2) + b; }, QuadEaseInOut: function(t, b, c, d) { if ((t /= d / 2) < 1) return c / 2 * t * t + b; return -c / 2 * ((--t) * (t - 2) - 1) + b; }, //三次的 CubicEaseIn: function(t, b, c, d) { return c * (t /= d) * t * t + b; }, CubicEaseOut: function(t, b, c, d) { return c * ((t = t / d - 1) * t * t + 1) + b; }, CubicEaseInOut: function(t, b, c, d) { if ((t /= d / 2) < 1) return c / 2 * t * t * t + b; return c / 2 * ((t -= 2) * t * t + 2) + b; }, //四次的 QuartEaseIn: function(t, b, c, d) { return c * (t /= d) * t * t * t + b; }, QuartEaseOut: function(t, b, c, d) { return -c * ((t = t / d - 1) * t * t * t - 1) + b; }, QuartEaseInOut: function(t, b, c, d) { if ((t /= d / 2) < 1) return c / 2 * t * t * t * t + b; return -c / 2 * ((t -= 2) * t * t * t - 2) + b; }, QuartEaseIn: function(t, b, c, d) { return c * (t /= d) * t * t * t * t + b; }, QuartEaseOut: function(t, b, c, d) { return c * ((t = t / d - 1) * t * t * t * t + 1) + b; }, QuartEaseInOut: function(t, b, c, d) { if ((t /= d / 2) < 1) return c / 2 * t * t * t * t * t + b; return c / 2 * ((t -= 2) * t * t * t * t + 2) + b; }, //正弦的 SineEaseIn: function(t, b, c, d) { return -c * Math.cos(t / d * (Math.PI / 2)) + c + b; }, SineEaseOut: function(t, b, c, d) { return c * Math.sin(t / d * (Math.PI / 2)) + b; }, SineEaseInOut: function(t, b, c, d) { return -c / 2 * (Math.cos(Math.PI * t / d) - 1) + b; }, ExpoEaseIn: function(t, b, c, d) { return (t == 0) ? b : c * Math.pow(2, 10 * (t / d - 1)) + b; }, ExpoEaseOut: function(t, b, c, d) { return (t == d) ? b + c : c * (-Math.pow(2, -10 * t / d) + 1) + b; }, ExpoEaseInOut: function(t, b, c, d) { if (t == 0) return b; if (t == d) return b + c; if ((t /= d / 2) < 1) return c / 2 * Math.pow(2, 10 * (t - 1)) + b; return c / 2 * (-Math.pow(2, -10 * --t) + 2) + b; }, CircEaseIn: function(t, b, c, d) { return -c * (Math.sqrt(1 - (t /= d) * t) - 1) + b; }, CircEaseOut: function(t, b, c, d) { return c * Math.sqrt(1 - (t = t / d - 1) * t) + b; }, CircEaseInOut: function(t, b, c, d) { if ((t /= d / 2) < 1) return -c / 2 * (Math.sqrt(1 - t * t) - 1) + b; return c / 2 * (Math.sqrt(1 - (t -= 2) * t) + 1) + b; }, ElasticEaseIn: function(t, b, c, d, a, p) { if (t == 0) return b; if ((t /= d) == 1) return b + c; if (!p) p = d * .3; if (!a || a < Math.abs(c)) { a = c; var s = p / 4; } else var s = p / (2 * Math.PI) * Math.asin(c / a); return -(a * Math.pow(2, 10 * (t -= 1)) * Math.sin((t * d - s) * (2 * Math.PI) / p)) + b; }, ElasticEaseOut: function(t, b, c, d, a, p) { if (t == 0) return b; if ((t /= d) == 1) return b + c; if (!p) p = d * .3; if (!a || a < Math.abs(c)) { a = c; var s = p / 4; } else var s = p / (2 * Math.PI) * Math.asin(c / a); return (a * Math.pow(2, -10 * t) * Math.sin((t * d - s) * (2 * Math.PI) / p) + c + b); }, ElasticEaseInOut: function(t, b, c, d, a, p) { if (t == 0) return b; if ((t /= d / 2) == 2) return b + c; if (!p) p = d * (.3 * 1.5); if (!a || a < Math.abs(c)) { a = c; var s = p / 4; } else var s = p / (2 * Math.PI) * Math.asin(c / a); if (t < 1) return -.5 * (a * Math.pow(2, 10 * (t -= 1)) * Math.sin((t * d - s) * (2 * Math.PI) / p)) + b; return a * Math.pow(2, -10 * (t -= 1)) * Math.sin((t * d - s) * (2 * Math.PI) / p) * .5 + c + b; }, //冲过头系列 BackEaseIn: function(t, b, c, d, s) { if (s == undefined) s = 1.70158; return c * (t /= d) * t * ((s + 1) * t - s) + b; }, BackEaseOut: function(t, b, c, d, s) { if (s == undefined) s = 1.70158; return c * ((t = t / d - 1) * t * ((s + 1) * t + s) + 1) + b; }, BackEaseInOut: function(t, b, c, d, s) { if (s == undefined) s = 1.70158; if ((t /= d / 2) < 1) return c / 2 * (t * t * (((s *= (1.525)) + 1) * t - s)) + b; return c / 2 * ((t -= 2) * t * (((s *= (1.525)) + 1) * t + s) + 2) + b; }, //弹跳系列 BounceEaseIn: function(t, b, c, d) { return c - Tween.BounceEaseOut(d - t, 0, c, d) + b; }, BounceEaseOut: function(t, b, c, d) { if ((t /= d) < (1 / 2.75)) { return c * (7.5625 * t * t) + b; } else if (t < (2 / 2.75)) { return c * (7.5625 * (t -= (1.5 / 2.75)) * t + .75) + b; } else if (t < (2.5 / 2.75)) { return c * (7.5625 * (t -= (2.25 / 2.75)) * t + .9375) + b; } else { return c * (7.5625 * (t -= (2.625 / 2.75)) * t + .984375) + b; } }, BounceEaseInOut: function(t, b, c, d) { if (t < d / 2) return Tween.BounceEaseIn(t * 2, 0, c, d) * .5 + b; else return Tween.BounceEaseOut(t * 2 - d, 0, c, d) * .5 + c * .5 + b; } } } var oDiv = document.querySelector('div') animate(oDiv, { 'paddingLeft': '50px', 'top': '60px', 'left': '60px', 'opacity': 0.6 }, 500, function() { }) // 获取DOM元素当前属性 function fetchComputedStyle(obj, str) { str = str.replace(/([A-Z])/g, function(match, $1) { return '-' + $1.toLowerCase() }) return getComputedStyle(obj)[str] } </script> </body> </html>