JavaScript dynamically adds styles (inline/embedded/external link, etc. rules)_javascript skills

function loadLink(url){
var link = document.createElement("link");
link.type = "text/css";
link.rel = "stylesheet";
link.href = url;
var head = document.getElmentsByTagName("head")[0];
head.appendChild(link);
}

function insertStyles(){
var doc,cssCode=[],cssText;
var len = arguments.length;
var head,style,firstStyle;
if(len == 1){
doc = document;
cssCode.push(arguments[0])
}else if(len == 2){
doc = arguments[0];
cssCode. push(arguments[1]);
}else{
alert("The function accepts at most two parameters!");
}
head = doc.getElementsByTagName("head")[0] ;
styles= head.getElementsByTagName("style");
if(styles.length == 0){
if(doc.createStyleSheet){//ie
doc.createStyleSheet();
}else{//FF
var tempStyle = doc.createElement("style");
tempStyle.setAttibute("type","text/css");
head.appendChild(tempStyle );
}
}
firstStyle = styles[0];
cssText=cssCode.join("n");
if(! "v1"){//opacity compatible
var str = cssText.match(/opacity:(d?.d );/);
if(str!=null){
cssText = cssText.replace(str[0],"filter: alpha(opacity=" pareFloat(str[1])*100 ")");
}
}
if(firstStyle.styleSheet){
firstStyle.styleSheee.cssText = cssText;
}else if(doc.getBoxObjectFor){
firstStyle.innerHTML = cssText;
}else{
firstStyle.appendChild(doc.createTextNode(cssText));
}
}

var addStyle=function (ele,str){
var s = ele.getAttribute("style"),styles;
if(str && typeof str === "string"){
if(! s){
ele.style.cssText = str;
}else{
if(s == '[object]'){//IE6/7 e.getAttribute("style") returns [ object]
s=ele.style.cssText;
}
styles= trim(s).split(";");
for (var i=0,len=styles.length; ivar style_i=trim(styles[i]);
var attr=style_i.split(":")[0];
if(str.indexOf(attr) >-1){
styles[i]="";
}else{
styles[i]=style_i;
}
}
ele.style.cssText= styles.join("") ";" str;
}
}
}

var hasClass=function (ele,value){
var rclass = /[ntr]/g,
value=" " value " ";
return (ele.nodeType==1)&&(" " ele.className " ").replace(rclass," ").indexOf(value)>-1;
}
var trim=function (val){
return val.replace(/(^s )|( s $)/g,"");
}
var addClass=function(ele,value){
var rspace = /s /,classNames,getClass;
if(value&&typeof value == = "string"){
classNames = value.split(rspace);
if(ele.nodeType === 1){
if(!ele.className && classNames.length == 1){
ele.className = value;
}else{
getClass = " " ele.className " ";
for(var i=0,len=classNames.length; ivar cname=classNames[i];
if(!hasClass(ele,cname)){
getClass = cname " ";
}
}
ele.className = trim(getClass);
}
}
}
}
var removeClass=function(ele,value){
var rclass = /[ntr]/g,classNames,getClass ;
if((value&&typeof value === "string")||value === undefined){
classNames = (value||"").split(rspace);
if(ele. nodeType === 1 && ele.className){
if(value){//There is a class to be removed
getClass = " " ele.className " ".replace(rclass," ");/ / Spaces left and right, in order to make the categories in the class equal, facilitate subsequent replacement
for(var i=0,len=classNames.length; igetClass = getClass.replace(" " classNames[i] " "," ")
}
ele.className=trim(getClass);
}else{//Remove all classes if they do not exist
ele.className = "";
}
}
}
}
var toggleClass=function(ele,value){
if(typeof value === "string"){
if(hasClass (ele,value)){
removeClass(ele,value);
}else{
addClass(ele,value);
}
}
}