async await 代替promise

const request = require('request');

const makeRequest = async () {
  try {
    let msg = await  __get();
    console.log(msg);
  } catch(err) {
    console.log(err);
  }

  # promise的写法
  // __get()
  //   .then(msg=>{
  //     console.log(msg);
  //   })
  //   .catch(err=>{
  //     console.log('error');
  //     console.log(err);
  //   })

}

function __get(){
  return new Promise((resolve, reject) => {
    request.get('http://127.0.0.1:9090/test',(err, res, body) => {
      if(err){
        reject(err);
      }else if(res.statusCode == 200){
        resolve(body); //success
      }else {
        reject("服务端异常";

}

makeRequest()

• 可以直接用try…catch来捕获promise中的reject错误异常。而不在用then…catch捕获。