The fade in and fade out effect is often used in daily projects. Unfortunately, native JS does not have a similar method, and sometimes small pages are not worth introducing a jQuery library, so I wrote one myself. It has been encapsulated and is useful. Friends, you can use it directly. There is also a method for setting element transparency in the code. It is set according to IE rules (0~100). If it is changed to the standard setting method (0.00~1.00), please consider floating point to accurately express the difference when using it below.
Parameter description:
Both fadeIn() and fadeOut() have three parameters. The first one is event, which is required; the second one is fade speed, which is a positive integer. You can weigh the size by yourself. It is optional. Parameter; the third one is to specify the transparency value to fade in and out to (similar to fadeTo() in jQuery), a positive integer value from 0 to 100, which is also an optional parameter.
Key code:
//淡入效果(含淡入到指定透明度) function fadeIn(elem, speed, opacity){ /* * 参数说明 * elem==>需要淡入的元素 * speed==>淡入速度,正整数(可选) * opacity==>淡入到指定的透明度,0~100(可选) */ speedspeed = speed || 20; opacityopacity = opacity || 100; //显示元素,并将元素值为0透明度(不可见) elem.style.display = 'block'; iBase.SetOpacity(elem, 0); //初始化透明度变化值为0 var val = 0; //循环将透明值以5递增,即淡入效果 (function(){ iBase.SetOpacity(elem, val); val += 5; if (val <= opacity) { setTimeout(arguments.callee, speed) } })(); } //淡出效果(含淡出到指定透明度) function fadeOut(elem, speed, opacity){ /* * 参数说明 * elem==>需要淡入的元素 * speed==>淡入速度,正整数(可选) * opacity==>淡入到指定的透明度,0~100(可选) */ speedspeed = speed || 20; opacityopacity = opacity || 0; //初始化透明度变化值为0 var val = 100; //循环将透明值以5递减,即淡出效果 (function(){ iBase.SetOpacity(elem, val); val -= 5; if (val >= opacity) { setTimeout(arguments.callee, speed); }else if (val < 0) { //元素透明度为0后隐藏元素 elem.style.display = 'none'; } })(); }
Rendering:
copy the code directly to see the effect
原生JS实现淡入淡出效果 <script> window.onload = function(){ //底层共用 var iBase = { Id: function(name){ return document.getElementById(name); }, //设置元素透明度,透明度值按IE规则计,即0~100 SetOpacity: function(ev, v){ ev.filters ? ev.style.filter = 'alpha(opacity=' + v + ')' : ev.style.opacity = v / 100; } } //淡入效果(含淡入到指定透明度) function fadeIn(elem, speed, opacity){ /* * 参数说明 * elem==>需要淡入的元素 * speed==>淡入速度,正整数(可选) * opacity==>淡入到指定的透明度,0~100(可选) */ speedspeed = speed || 20; opacityopacity = opacity || 100; //显示元素,并将元素值为0透明度(不可见) elem.style.display = 'block'; iBase.SetOpacity(elem, 0); //初始化透明度变化值为0 var val = 0; //循环将透明值以5递增,即淡入效果 (function(){ iBase.SetOpacity(elem, val); val += 5; if (val <= opacity) { setTimeout(arguments.callee, speed) } })(); } //淡出效果(含淡出到指定透明度) function fadeOut(elem, speed, opacity){ /* * 参数说明 * elem==>需要淡入的元素 * speed==>淡入速度,正整数(可选) * opacity==>淡入到指定的透明度,0~100(可选) */ speedspeed = speed || 20; opacityopacity = opacity || 0; //初始化透明度变化值为0 var val = 100; //循环将透明值以5递减,即淡出效果 (function(){ iBase.SetOpacity(elem, val); val -= 5; if (val >= opacity) { setTimeout(arguments.callee, speed); }else if (val < 0) { //元素透明度为0后隐藏元素 elem.style.display = 'none'; } })(); } var btns = iBase.Id('demo').getElementsByTagName('input'); btns[0].onclick = function(){ fadeIn(iBase.Id('fadeIn')); } btns[1].onclick = function(){ fadeOut(iBase.Id('fadeOut'),40); } btns[2].onclick = function(){ fadeOut(iBase.Id('fadeTo'), 20, 10); } } </script>脚本之家是国内专业的网站建设资源、脚本编程学习类网站,提供asp、php、asp.net、javascript、jquery、vbscript、dos批处理、网页制作、网络编程、网站建设等编程资料。
脚本之家
脚本之家是国内专业的网站建设资源、脚本编程学习类网站,提供asp、php、asp.net、javascript、jquery、vbscript、dos批处理、网页制作、网络编程、网站建设等编程资料。
脚本之家
脚本之家是国内专业的网站建设资源、脚本编程学习类网站,提供asp、php、asp.net、javascript、jquery、vbscript、dos批处理、网页制作、网络编程、网站建设等编程资料。

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