SOURCE

//jq提供ajax请求
// $.ajax({
//     type: "get",
//     url: "",
//     data: {},
//     dataType: "json",
//     success: function (data) {
//     }
// })

let $ = {};
$.__proto__.ajax = function({type='get',url,data,dataType='HTML',success}){
    let xhr = new XMLHttpRequest();
    if(type === 'get' || type === 'GET'){
        xhr.open(type,data?`${url}?${data}`:url);
        xhr.send(null)
    }else if(type === 'post' || type === 'POST'){
        xhr.open(type,url);
        xhr.send(data)
        xhr.setRequestHeader('Content-Type','application/x-www-form-urlencoded')
    }
    
    xhr.onreadystatechange = function(){
        if(xhr.readyState === 4 && xhr.status === 200){
            if(dataType === 'HTML'){
                success(xhr.responseText)
            }else if(dataType === 'JSON'){
                success(JSON.parse(xhr.responseText))
            }
        }
    }
}