//模擬jQuery封裝ajax 暫不考慮跨域和默認(rèn)返回?cái)?shù)據(jù)類型為JSON
function ajax(obj){
    var temp={
        type:'get',
        url:"#",
        data:{},
        success:function(param){console.log(param)}
    };

    for(var key in obj){
        temp[key]=obj[key];
    }

    var data='';
    for(var key in temp.data){
        data+=`${key}=${temp.data[key]}&`;
    }
    if(data){
        data=data.substr(0,data.length-1);
    }
    var xhr=new XMLHttpRequest();
    xhr.onreadystatechange=function(){
        if(xhr.readyState===4){
            if(xhr.status===200){
                var param=JSON.parse(xhr.responseText);
                temp.success(param);
            }
        }
    };
    var main=null;
    if(temp.type==='get'){
        temp.url+="?"+data;
    }else{
        main=data;
        xhr.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
    }
    xhr.open(temp.type,temp.url,true);
    xhr.send(main);
}