ajax 封装(备忘)

function openLink(o){	
	var XHR,
		config = (typeof o === 'object' && o!=null)?o : {},
		scope = config.scope||window,
		method = config.method||'GET',
		cb = typeof config.callback === 'function' ? config.callback : function(){},
		url = config.url,
		params = config.params||{},
		p = null,
		addURLParam = function(url,key,value){
			url += (url.indexOf('?') == -1 ? '?' : '&');
			url += encodeURIComponent(key) + '=' + encodeURIComponent(value);
			return url;
		},
		timeout = 30000;//30s
		
	if(typeof url !== 'string'){
		throw new Error('配置的请求地址错误!');
	}
	
	if(typeof XMLHttpRequest != 'undefined'){
		XHR = new XMLHttpRequest();
	}else if(typeof ActiveXObject != 'undefined'){
		var versions = ['MSXML2.XMLHTTP.3.0','Msxml2.XMLHTTP.6.0','MSXML2.XMLHTTP','Microsoft.XMLHTTP'];
		for(var i=0,len=versions.length;i<len;i++){
			try{
				XHR = new ActiveXObject(versions[i]);
				break;
			}catch(ex){
				
			}
		}
	}else{
		throw new Error('您的浏览器不能创建XHR对象!');
	}
	
	var t = setTimeout(function(){
		XHR.abort();
		throw new Error('timeout!');
	},timeout);
	
	XHR.onreadystatechange = function(){
		if(XHR.readyState == 4){
			if((XHR.status >= 200 && XHR.status < 300) || XHR.status == 304){
				//success
				//XHR.responseText
				clearTimeout(t);
				cb.call(scope,XHR.responseText);
			}else{
				//exception
				throw new Error('Request is unsuccessfull: '+ XHR.status);
			}
		}
	}
	if(method.toUpperCase() == 'GET'){
		for(var f in params){
			url = addURLParam(url,f,params[f]);
		}
	}else if(method.toUpperCase() == 'POST'){
		var a = [];
		for(var f in params){
			a.push(f+'='+encodeURIComponent(params[f]));
		}
		p = a.join('&');
	}
	
	XHR.open(method,url,true);
	XHR.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded; charset=UTF-8');
	XHR.send(p);
}

 

使用：

<script type="text/javascript">
		openLink({
			method : 'post',
			url : 'data/test.do',
			params : {e:'中文abc123',r:5},
			callback : function(responseText){
				var o = eval('('+responseText+')');
				alert(o.success);
			}
		});
	</script>