js method to achieve multiple different motion effects on the same page

js method to achieve multiple different motion effects on the same page_javascript skills

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Release： 2016-05-16 16:04:58

Original

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The example in this article describes the method of using js to achieve multiple different motion effects on the same page. Share it with everyone for your reference. The specific analysis is as follows:

Point 1:

function getstyle(obj,name){
if(obj.currentStyle){
return obj.currentStyle[name];
}else{
return getComputedStyle(obj,false)[name];
}
}

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Get the value from the style sheet based on the id and attribute name.

Point 2:

if(attr == "opacity"){
cur = Math.round(parseFloat(getstyle(obj,attr))*100);
}else{
cur = parseInt(getstyle(obj,attr));
}

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If you set a transparency value, you need to use parseFloat because there may be decimal points. Then there may be decimals. Use the round method to round off.

If you set a non-transparency value, use parseInt to get only the numerical part

Other points of note have been mentioned in the previous articles and will not be repeated here.

Finally, add the code:

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>无标题文档</title>
<style>
body,ul,li{margin:0; padding:0;}
#runs li{width:80px; height:80px; background:#06c;
list-style:none; margin:10px; border:1px solid #000;
filter:alpha(opacity=30); opacity:0.3;}
</style>
<script>
window.onload = function(){
 var runs = document.getElementById("runs");
 var runs_li = runs.getElementsByTagName("li");
  runs_li[0].onmouseover = function(){
   startrun(this,"width",300);
  }
  runs_li[0].onmouseout = function(){
   startrun(this,"width",80);
  }
  runs_li[1].onmouseover = function(){
   startrun(this,"height",300);
  }
  runs_li[1].onmouseout = function(){
   startrun(this,"height",80);
  }
  runs_li[2].onmouseover = function(){
   startrun(this,"fontSize",50);
  }
  runs_li[2].onmouseout = function(){
   startrun(this,"fontSize",14);
  }
  runs_li[3].onmouseover = function(){
   startrun(this,"opacity",100);
  }
  runs_li[3].onmouseout = function(){
   startrun(this,"opacity",30);
  }
}
function startrun(obj,attr,target){
 clearInterval(obj.timer);
 obj.timer = setInterval(function(){
 var cur = 0;
 if(attr == "opacity"){
  cur = Math.round(parseFloat(getstyle(obj,attr))*100);
 }else{
  cur = parseInt(getstyle(obj,attr));
 }
 var speed = (target - cur)/8;
 speed = speed>0&#63;Math.ceil(speed):Math.floor(speed);
  
  if(cur == target){
   clearInterval(obj.timer);
  }else{
   if(attr == "opacity"){
    obj.style.filter='alpha(opacity='+(cur+speed)+')';
    obj.style.opacity=(cur+speed)/100;
   }else{
    obj.style[attr] = cur+speed+"px";
   }
  }
 },30);
}
function getstyle(obj,name){
 if(obj.currentStyle){
  return obj.currentStyle[name];
 }else{
  return getComputedStyle(obj,false)[name];
 }
}
</script>
</head>
<body>
<ul id="runs">
 <li style="top:0">1</li>
 <li style="top:90px;">2</li>
 <li style="top:180px;">3</li>
 <li style="top:270px;">4</li>
</ul>
</body>
</html>

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I hope this article will be helpful to everyone’s JavaScript programming design.