在页面中动态载入外部javascript

有时候需要在网页中某个div载入之后，动态引入一段javascript，IE下的解决方案：

newjs. onreadystatechange = function ( ) {
if (newjs. readyState == 'loaded' ) {
// ready!
}
}
 
newjs. onload = function ( ) {
// ready!
}

 主要利用了onload以及onreadystatechange事件。把这个加以利用，也能动态载入外部css。下面是同时适合Ie/firefox的写法。

var css;
function include_css (css_file ) {
var html_doc = document. getElementsByTagName ( 'head' ) [ 0 ];
css = document. createElement ( 'link' );
css. setAttribute ( 'rel', 'stylesheet' );
css. setAttribute ( 'type', 'text/css' );
css. setAttribute ( 'href', css_file );
html_doc. appendChild (css );
 
// alert state change
css. onreadystatechange = function ( ) {
if (css. readyState == 'complete' ) {
alert ( 'CSS onreadystatechange fired' );
}
}
css. onload = function ( ) {
alert ( 'CSS onload fired' );
}
return false;
}
 
var js;
function include_js (file ) {
var html_doc = document. getElementsByTagName ( 'head' ) [ 0 ];
js = document. createElement ( 'script' );
js. setAttribute ( 'type', 'text/javascript' );
js. setAttribute ( 'src', file );
html_doc. appendChild (js );
 
js. onreadystatechange = function ( ) {
if (js. readyState == 'complete' ) {
alert ( 'JS onreadystate fired' );
}
}
 
js. onload = function ( ) {
alert ( 'JS onload fired' );
}
return false;
}