个回答

• Einson

  2016-07-29 17:25:10

  已采纳

  定义和用法

  animation-timing-function 规定动画的速度曲线。

  速度曲线定义动画从一套 CSS 样式变为另一套所用的时间。

  速度曲线用于使变化更为平滑。

  
  

  默认值：

  ease    

  
  

  
  

  继承性：

  no    

  
  

  JavaScript 语法：

  object.style.animationTimingFunction="linear"    

  
  

  语法

  animation-timing-function: value;
  

  animation-timing-function 使用名为三次贝塞尔（Cubic Bezier）函数的数学函数，来生成速度曲线。您能够在该函数中使用自己的值，也可以预定义的值：

  
  

  值                              描述

  linear                          |  动画从头到尾的速度是相同的。    

  ease                           | 默认。动画以低速开始，然后加快，在结束前变慢。       

  ease-in                       | 动画以低速开始。       

  ease-out                    |  动画以低速结束。    

  ease-in-out                | 动画以低速开始和结束。     

  cubic-bezier(n,n,n,n)   | 在 cubic-bezier 函数中自己的值。可能的值是从 0 到 1 的数值。    

  实例 1

  为了更好地理解不同的定时函数值，这里提供了设置五个不同值的五个不同的 div 元素：

  /* W3C 和 Opera: */#div1 {animation-timing-function: linear;}
  #div2 {animation-timing-function: ease;}
  #div3 {animation-timing-function: ease-in;}
  #div4 {animation-timing-function: ease-out;}
  #div5 {animation-timing-function: ease-in-out;}/* Firefox: */#div1 {-moz-animation-timing-function: linear;}
  #div2 {-moz-animation-timing-function: ease;}
  #div3 {-moz-animation-timing-function: ease-in;}
  #div4 {-moz-animation-timing-function: ease-out;}
  #div5 {-moz-animation-timing-function: ease-in-out;}/* Safari 和 Chrome: */#div1 {-webkit-animation-timing-function: linear;}
  #div2 {-webkit-animation-timing-function: ease;}
  #div3 {-webkit-animation-timing-function: ease-in;}
  #div4 {-webkit-animation-timing-function: ease-out;}
  #div5 {-webkit-animation-timing-function: ease-in-out;}

  实例 2

  与上例相同，但是通过 cubic-bezier 函数来定义速度曲线：

  /* W3C 和 Opera: */#div1 {animation-timing-function: cubic-bezier(0,0,1,1);}
  #div2 {animation-timing-function: cubic-bezier(0.25,0.1,0.25,1);}
  #div3 {animation-timing-function: cubic-bezier(0.42,0,1,1);}
  #div4 {animation-timing-function: cubic-bezier(0,0,0.58,1);}
  #div5 {animation-timing-function: cubic-bezier(0.42,0,0.58,1);}/* Firefox: */#div1 {-moz-animation-timing-function: cubic-bezier(0,0,1,1);}
  #div2 {-moz-animation-timing-function: cubic-bezier(0.25,0.1,0.25,1);}
  #div3 {-moz-animation-timing-function: cubic-bezier(0.42,0,1,1);}
  #div4 {-moz-animation-timing-function: cubic-bezier(0,0,0.58,1);}
  #div5 {-moz-animation-timing-function: cubic-bezier(0.42,0,0.58,1);}/* Safari 和 Chrome: */#div1 {-webkit-animation-timing-function: cubic-bezier(0,0,1,1);}
  #div2 {-webkit-animation-timing-function: cubic-bezier(0.25,0.1,0.25,1);}
  #div3 {-webkit-animation-timing-function: cubic-bezier(0.42,0,1,1);}
  #div4 {-webkit-animation-timing-function: cubic-bezier(0,0,0.58,1);}
  #div5 {-webkit-animation-timing-function: cubic-bezier(0.42,0,0.58,1);}
  

  
  

  
  

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