使用JQuery进行跨域请求_javascript技巧

$(document).ready(function(){
var container = $('#target');
container.attr('tabIndex','-1');
$('.ajaxtrigger').click(function(){
var trigger = $(this);
var url = trigger.attr('href');
if(!trigger.hasClass('loaded')){
trigger.append('');
trigger.addClass('loaded');
var msg = trigger.find('span::last');
} else {
var msg = trigger.find('span::last');
}
doAjax(url,msg,container);
return false;
});

function doAjax(url,msg,container){
// if the URL starts with http
if(url.match('^http')){
// assemble the YQL call
msg.removeClass('error');
msg.html(' (loading...)');
$.getJSON("http://query.yahooapis.com/v1/public/yql?"+
"q=select%20*%20from%20html%20where%20url%3D%22"+
encodeURIComponent(url)+
"%22&format=xml'&callback=?",
function(data){
if(data.results[0]){
var data = filterData(data.results[0]);
msg.html(' (ready.)');
container.
html(data).
focus().
effect("highlight",{},1000);
} else {
msg.html(' (error!)');
msg.addClass('error');
var errormsg = '

error: could not load the page.

';
container.
html(errormsg).
focus().
effect('highlight',{color:'#c00'},1000);
}
}
);
} else {
$.ajax({
url: url,
timeout:5000,
success: function(data){
msg.html(' (ready.)');
container.
html(data).
focus().
effect("highlight",{},1000);
},
error: function(req,error){
msg.html(' (error!)');
msg.addClass('error');
if(error === 'error'){error = req.statusText;}
var errormsg = 'There was a communication error: '+error;
container.
html(errormsg).
focus().
effect('highlight',{color:'#c00'},1000);
},
beforeSend: function(data){
msg.removeClass('error');
msg.html(' (loading...)');
}
});
}
}
function filterData(data){
// filter all the nasties out
// no body tags
data = data.replace(/\/body[^>]*>/g,'');
// no linebreaks
data = data.replace(/[\r|\n]+/g,'');
// no comments
data = data.replace(//g,'');
// no noscript blocks
data = data.replace(/