fetch API处置惩罚异步嵌套题目

我们昨天进修了async和await，晓得他是为了处置惩罚浏览器异步猎取的的！然则我们用fetch api的话要领会越发的简朴

async和await处置惩罚异步嵌套

function ajax(url){

          return new Promise(function(reslove,reject){
              let xmlHttp=new XMLHttpRequest();
              xmlHttp.open("get",url,true);
              xmlHttp.onreadystatechange=function(){
                  if(xmlHttp.readyState==4&&xmlHttp.status==200){
                      let data=JSON.parse(xmlHttp.responseText);
                      reslove(data);
                  }
              }
              xmlHttp.send(null);
          })
      }
      let uldom=document.getElementById("students");
      let url="http://192.168.0.57:8000/students.json";
      async function main(){
        let data=await ajax(url);
      
        let students=data;
        let html="";
        for(let i=0,l=students.length;i<l;i++){
            let name=students[i].name;
            let age=students[i].age;
            html+=`
            <li>姓名${name},岁数${age}</li>
            `
        }
        uldom.innerHTML=html;
      }
      main();

我们须要建立Promise函数来举行操纵，假如我们用fetch处置惩罚的话，会越发的轻易！

let uldom=document.getElementById("students");
      let url="http://192.168.0.57:8000/students.json";
        function main(){
            fetch(url).then(respone=>{
            return respone.json();
        }).then(data=>{
            let students=data;
            let html="";
            for(let i=0,l=students.length;i<l;i++){
                let name=students[i].name;
                let age=students[i].age;
                html+=`
                <li>姓名${name},岁数${age}</li>
                `
            }
            uldom.innerHTML=html;
        });
            
        }
        main();

不必建立Promise，直接挪用then()是否是比上边越发的简朴！

async、await连系fetch处置惩罚异步

let uldom=document.getElementById("students");
    let url="http://192.168.0.57:8000/students.json";  
    async function main(){
        let respone = await fetch(url);
        let student = await respone.json();
        let html="";
        for (let i=0,l=students.length;i<l;i++){
            let name=students[i].name;
            let age=students[i].age;
            html+=`
            <li>姓名${name},岁数${age}</li>
            `
        }
        uldom.innerHTML=html;
        }
    main()

觉得是否是很简朴！比上一种要领越发的简朴。