javascript promise 对象实例

下面是js简单的一个promise对象实例

// promise.js
let myFirstPromise = new Promise(function(resolve, reject){
  let x = 1;
  //let x = 6;
  if(x>3)
    resolve(`${x} > 3, succ`);
  else
    reject(`${x} < 3 fail`);
});

myFirstPromise.then(function(succMsg){
  console.log(succMsg); // succMsg 参数 是 resolve 返回的内容
}).catch(function(failMsg){
  console.log(failMsg); // failMsg 参数是 reject 返回的内容
});

运行结果

$ node promise.js
1 < 3 fail

参考： https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Promise