JS动态加载 js css

1.动态加载js

function loadScript( url ){ 
var script = document.createElement( "script" ); 
script.type = "type/javascipt"; 
script.src = url; 
document.getElementsByTagName( "head" )[0].appendChild( script ); 
}; 

2.动态加载CSS文件

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

3.动态加载CSS样式

if( flag ){ 
var style = document.createElement( "style" ); 
style.type = "text/css"; 
document.getElementsByTagName( "head" )[0].appendChild( style ); 
var sheet = document.styleSheets[0]; 
insertRules( sheet,"#gaga1","background:#f00",0 ); 
}; 

原文：http://www.cnblogs.com/jiechn/p/4200689.html