js FormData 关于后台数据获取的 的需要用from提交但是前台没有使用from 表单 需要在js里面转换使用FormData

var formData = new FormData();
function but(){

//获取省id
let List = sele[0].getElementsByTagName("option")[num-1].value
//获取市id
let Citylists = sele[1].getElementsByTagName("option")[nums-1].value
//获取区id
let Arealists = sele[2].getElementsByTagName("option")[nums-1].value


var name=text[0].value
var tel=text[1].value
var ing=text[2].value

formData.append('user_id',303);
formData.append('adds',ing);
formData.append('sheng',List);
formData.append('city', Citylists);
formData.append('quyu', Arealists);
formData.append('tel', tel);
formData.append('receiver', name);


var add=new XMLHttpRequest()
add.open("POST","https://exam.qhynice.top/index.php/Api/Address/add_adds?")
add.send(formData)
add.onreadystatechange=function(){
if(add.status==200 && add.readyState==4){
var adds=JSON.parse(decodeURI(add.responseText))
console.log(adds)
}
}


}