Home > Article > Web Front-end > How to operate JS to implement transparency gradient animation
This time I will show you how to operate JS to achieve transparency gradient animation. What are the precautions for operating JS to achieve transparency gradient animation? The following is a practical case, let’s take a look.
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>JS透明度变化效果</title> <style> body{ margin: 0px; padding: 0px; } .redb{ width:200px; height: 200px; background: red; filter:alpha(opacity=30); opacity: 0.3; } </style> </head> <body> <p class="redb" id="opbtn"></p> <script> window.onload = function(){ var opp = document.getElementById("opbtn"); opp.onmouseover = function(){ startMove(100); } opp.onmouseout = function(){ startMove(30); } } var timer = null; var alpha = 30; var speed = 0; function startMove(opTarget){ clearInterval(timer); var opp = document.getElementById("opbtn"); timer = setInterval(function(){ if(alpha<opTarget){ speed = 10; } else if(alpha>opTarget){ speed = -10; } if(alpha==opTarget){ clearInterval(timer); } else{ alpha += speed; opp.style.opacity = alpha/100; opp.style.filter = 'alpha(opacity='+alpha+')'; } },100); } </script> </body> </html>
Summary:
1. The difference between filter and opacity: w3c standard transparency is opacity, filter can only be used by IE, other browsers support opacity2 . When changing the transparency, the transparency value cannot be obtained through a method similar to offsetLeft, so you need to create a separate variable
3. Don’t forget to assign the
timer to timer
Using the cache call chain to implement JS method overloading steps Detailed explanation
The above is the detailed content of How to operate JS to implement transparency gradient animation. For more information, please follow other related articles on the PHP Chinese website!