hm-toutiao-mobile-128
/
test.html

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <script>
    // Promise相关API
    // Promise
    // p.then
    // p.catch

    // Promise.resolve() 把数据包装为Promise对象并且得到正确结果
    // Promise.reject() 把错误数据包装为Promise对象并且得到异常结果

    function getResult() {
      return new Promise(function (resolve, reject) {
        setTimeout(() => {
          resolve('hello')
        }, 1000)
      })
    }

    getResult().then(function (ret) {
      console.log(ret)
      // return 'nihao'
      // return new Promise(function (resolve) {
      //   resolve('nihao')
      // })
      // return Promise.resolve('nihao')
      // ---------------------------------------------
      return Promise.reject('nihao')
      // return new Promise(function (resolve, reject) {
      //   reject('nihao')
      // })
    }).then(function (ret) {
      console.log(ret)
    }).catch(function (err) {
      console.log(err, '----------')
    })

    // Promise.resolve = function (param) {
    //   return new Promise(function (resolve) {
    //     resolve(param)
    //   })
    // }

    // Promise.reject = function (param) {
    //   return new Promise(function (resolve, reject) {
    //     reject(param)
    //   })
    // }
  </script>
</body>

</html>