如果您可以使用q库https://github.com/kriskowal/q 它有q. allsettle()方法可以解决这个问题 您可以根据每个承诺的状态来处理它，可以是完全提交的，也可以是拒绝的 所以

existingPromiseChain = existingPromiseChain.then(function() {
var arrayOfPromises = state.routes.map(function(route){
  return route.handler.promiseHandler();
});
return q.allSettled(arrayOfPromises)
});

existingPromiseChain = existingPromiseChain.then(function(arrayResolved) {
//so here you have all your promises the fulfilled and the rejected ones
// you can check the state of each promise
arrayResolved.forEach(function(item){
   if(item.state === 'fulfilled'){ // 'rejected' for rejected promises
     //do somthing
   } else {
     // do something else
   }
})
// do stuff with my array of resolved promises, eventually ending with a res.send();
});

这就是Promise。一切都是为了工作而设计。如果只有一个promise reject()，整个方法立即失败。

有一些用例可能需要Promise。都是为了让承诺落空。要做到这一点，只需不要在承诺中使用任何reject()语句。然而，为了确保你的应用程序/脚本不会在任何一个底层承诺从未得到响应的情况下冻结，你需要给它设置一个超时。

function getThing(uid,branch){
    return new Promise(function (resolve, reject) {
        xhr.get().then(function(res) {
            if (res) {
                resolve(res);
            } 
            else {
                resolve(null);
            }
            setTimeout(function(){reject('timeout')},10000)
        }).catch(function(error) {
            resolve(null);
        });
    });
}

正如@jib所说，

的承诺。要么全部，要么一无所有。

不过，您可以控制某些“允许”失败的承诺，我们希望继续进行。

为例。

  Promise.all([
    doMustAsyncTask1,
    doMustAsyncTask2,
    doOptionalAsyncTask
    .catch(err => {
      if( /* err non-critical */) {
        return
      }
      // if critical then fail
      throw err
    })
  ])
  .then(([ mustRes1, mustRes2, optionalRes ]) => {
    // proceed to work with results
  })

在allsettle的帮助下，我们现在可以读取的状态 每个承诺都是，并单独处理每个错误，而不会丢失任何关键信息

const promises = [
    fetch('/api/first'), // first
    fetch('/api/second') // second
];

最简单的方法是处理错误

const [firstResult, secondResult] = await Promise.allSettled(promises)


 // Process first
 if (firstResult.status === 'rejected') {
   const err = firstResult.reason
   // Here you can handle error
 } else {
   const first = firstResult.value
 }

  // Process second
 if (secondResult.status === 'rejected') {
   const err = secondResult.reason
   // Here you can handle error
 } else {
   const second = secondResult.value
 }

处理错误的好方法

const results = await Promise.allSettled(promises);
const [first, second] = handleResults(results)


function handleResults(results) {
  const errors = results.filter(result => result.status === 'rejected').map(result => result.reason)

  if (errors.length) {
    // Aggregate all errors into one
    throw new AggregateError(errors)
  }

  return results.map(result => result.value)
}

Promise.allSettled

而不是承诺。都使用Promise。等待所有承诺的解决，不管结果如何

let p1 = new Promise(resolve => resolve("result1")); let p2 = new Promise((resolve,reject) => reject('some trouble ')); let p3 = new Promise(resolve => resolve("result3")); //返回每个promise状态和值的信息 Promise.allSettled ((p1, p2, p3))。然后(结果= > console.log(结果));

Polyfill

if (! promise . allsettle) { const rejectHandler = reason => ({status: 'rejected'， reason}); const resolveHandler = value =>({状态:'已完成'，value}); 的承诺。allsettle =函数(承诺){ const convertedPromises = promises .map(p =>承诺。resolve(p)。然后(resolveHandler rejectHandler)); 返回Promise.all (convertedPromises); }; ｝

const promise1 = Promise.resolve(3);
const promise2 = new Promise((resolve, reject) => setTimeout(reject, 100, 'foo'));
const promises = [promise1, promise2];
let sum = 0;
let promiseErrorArr = [];

Promise.allSettled(promises)
.then((results) => {
          results.forEach(result => {
            if (result.status === "rejected") {
              sum += 1;
              promiseErrorArr.push(result)
            }
          })
    return ( (sum>0) ? promiseFailed() : promisePassed())
})

function promiseFailed(){
  console.log('one or all failed!')
  console.log(promiseErrorArr)
}

function promisePassed(){
  console.log('all passed!')
}

// expected output:
// "one or all failed!"
// Array [Object { status: "rejected", reason: "foo" }]