Javascript代码片段

<script type="text/javascript">
/*getElementsByClassName*/
function getElementsByClassName(node,className){
if(node.getElementsByClassName){
return node.getElementsByClassName(className);
} else {
var results=new Array();
var elems=node.getElementsByTagName("*");
for(var i=0;i<elems.length;i++){
if(elems[i].className.indexOf(className)!=-1){
results[results.length]=elems[i];
 }
 }
return results;
 }
}
</script>

共享onload事件

function addLoadEvent(func){
var oldonload=window.onload;
if(typeof window.onload != "function"){
window.onload=func;
} else {
window.onload=function(){
oldonload();
func();
}
}
}

 

insertAfter(newElement,targetElement) 

function insertAfter(newElement,targetElement){
var parent=targetElement.parentNode;
if(parent.lastChild==targetElement){
parent.appendChild=newElement;
} else {
parent.insertBefore(newElement,targetElement.nextSibling);
}
}

 

初始化XMLHttpRequest对象

function getHTTPObject(){
if(typeof XMLHttpRequest =="undefined"){
XMLHttpRequest=function(){
try{ return new ActiveXObject("Msxml2.XMLHTTP.6.0");}
catch(e){}
try{ return new ActiveXObject("Msxml2.XMLHTTP.3.0");}
catch(e){}
try{ return new ActiveXObject("Msxml2.XMLHTTP");}
catch(e){}
return false;
}
}
return new XMLHttpRequest();
}

addClass

function addClass(elem,className){
if(!elem.className){
elem.className=className;
} else {
var newClassName=elem.className;
newClassName+=" ";
newClassName+=className;
elem.className=newClassName;
}
}

 

fadeIn、fadeOut、setOpacity

/**
 *@name:setOpacity
 *@description:设置元素的透明度
 *@arguments:elem==>元素，opacity==>目标透明度
*/

function setOpacity(elem,opacity){
if(elem.filters){//IE透明滤镜
elem.style.filter="alpha(opacity="+opacity+")";
} else {
elem.style.opacity=opacity/100;
 }
}


/**
 *@name:fadeIn
 *@description:淡入效果
 *@arguments:elem==>元素，speed==>速度（毫秒），opacity==>目标透明度
*/
function fadeIn(elem,speed,opacity){
var peed=speed || 20;
var opacity=opacity || 100;
//清除真在执行的fade
if(elem.fade){
 clearTimeout(elem.fade);
 }
//对要处理的元素初始化
elem.style.display="block";

//初始化透明度值0
var val=0;
//循环改变透明值直到透明值等于目标透明值停止，每次增加剩余的1/10
(function(){
setOpacity(elem,val);//调用设置透明度的函数
val+=Math.ceil((opacity-val)/10);
if(val<opacity){
elem.fade=setTimeout(arguments.callee,speed); //调用自身来不断改变透明值并不断调用setOpacity来设置新的透明值
 }
 })();
}

/**
 *@name:fadeOut
 *@description:淡出效果
 *@arguments:elem==>元素，speed==>速度（毫秒），opacity==>目标透明度
*/

function fadeOut(elem,speed,opacity){
var speed=speed || 20;
var opacity=opacity || 0;
//清除真在执行的fade
if(elem.fade){
 clearTimeout(elem.fade);
 }
//初始化透明值
var val=100;
//循环改变透明值直到透明值等于目标透明值停止,每次减少剩余的1/10
(function(){
setOpacity(elem,val);//调用设置透明度的函数
val-=Math.ceil((val-opacity)/10);
if(val>opacity){
elem.fade=setTimeout(arguments.callee,speed); //调用自身来不断改变透明值并不断调用setOpacity来设置新的透明值
} else if(val<=0){
elem.style.display="none";//透明值达到目标值后隐藏
 }
 })();
}

js动态加载

 1 var JsLoader = {
 2     load: function(sUrl, fCallback) {
 3         var _script = document.createElement("script");
 4         _script.setAttribute("type", "text/javascript");
 5         _script.setAttribute("src", sUrl);
 6         document.getElementsByTagName("head")[0].appendChild(_script);
 7 
 8         if (/msie/.test(window.navigator.userAgent.toLowerCase())) {
 9             _script.onreadystatechange = function() {
                 if (this.readyState == "loaded" || this.readyState == "complete") {
                     fCallback();
                 }
             };
         } else if (/gecko/.test(window.navigator.userAgent.toLowerCase())) {
             _script.onload = function() {
                 fCallback();
             };
         } else {
             fCallback();
         }
     }
 }