//1.创建处理客户传递数据的函数

function resolveData(data) {

var arr=[]

for (let k in data){

var str = k + '='+data[k]

arr.push(str)

}

return arr.join('&')

}

//2.封装处理函数

function itheima(options) {

var xhr = new XMLHttpRequest ()

var qs = resolveData(options.data) //查询参数

if(options.method.toUpperCase()=== 'GET'){  //判断提交类型

xhr.open(options.method,option.url+'?'+qs)

xhr.send()

}

else if(options.method.toUpperCase()==='post'){

xhr.open(options.method,options.url)

xhr.setRequestHeader('Conten-Type','application/x-www-form-urlencoded')

xhr.send(qs)

}

xhr.onreadystatechange = function () {

if(xhr.readystate === 4 && xhr.status === 200){

    let result = JSON.parse(xhr.responseText)

    options.success(result)

      }

  }

}