我正在使用异步 waterfall 。当我的函数之一调用 callback(err) 时,会调用我的自定义异步回调。在那里我抛出一个错误,希望它会被异步周围的 try 块捕获,但这并没有发生。

try {
    async.waterfall([function1, function2], myAsyncCallback);
}
catch(err) {
    console.log("THIS CODE IS NEVER EXECUTED.");
}

var function1 = function() {
...
   //some error occurs:
   callback(new Error(errMsg), errMsg);
...
}

var function2 = function() {
...
}

function myAsyncCallback(err, result) {
    console.log("This code gets executed.");
    if (err) {
            console.log("This code gets executed too.");
            throw new Error("I want this error caught at the top around the catch around async.waterfall()");
        }
}

最佳答案

https://runkit.com/imjosh/async-try-catch/2.0.0

var async = require('async');

try {
  async.waterfall([function1, function2], myAsyncCallback);
}
catch(err) {
  errorHandler(err);
}

function function1(callback) {
  console.log('in fn1')
  callback(null,'fn1');
}

function function2(fn1, callback) {
  console.log('in fn2')
  callback(null, fn1 + 'fn2');
}

function myAsyncCallback(err, result) {
    if (err) {
      console.error('There was an error: ' + err);
      return;
    }
    //an error occurs. this gets caught by the outer try block
    //var foo = outer; //oops, outer is not defined. This throws an error

    //same scenario but inside an async function
    //can't/won't be caught by the outer try block
    setTimeout(function(){
        try{ //need try here
          var foo = inner; //oops, inner is not defined. This throws an error
        }
        catch(err) {
          errorHandler(err);
       }
    }, 1000);

    console.log('Result was: ' + result);
}

function errorHandler(err){
  //Make error handler a function that can be called from either catch
  console.log('caught error: ' + err);
}

关于javascript - Node 异步和异常处理,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/40661730/

10-12 00:00
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