在Mohsen的回答中指出，在ES6中可以使用类来扩展错误。这要容易得多，而且它们的行为与本机错误更一致……但不幸的是，如果你需要支持前es6版本的浏览器，在浏览器中使用它并不是一件简单的事情。下面是关于如何实施的一些注意事项，但与此同时，我建议一个相对简单的方法，它包含了其他答案中的一些最好的建议:

function CustomError(message) {
    //This is for future compatibility with the ES6 version, which
    //would display a similar message if invoked without the
    //`new` operator.
    if (!(this instanceof CustomError)) {
        throw new TypeError("Constructor 'CustomError' cannot be invoked without 'new'");
    }
    this.message = message;

    //Stack trace in V8
    if (Error.captureStackTrace) {
       Error.captureStackTrace(this, CustomError);
    }
    else this.stack = (new Error).stack;
}
CustomError.prototype = Object.create(Error.prototype);
CustomError.prototype.name = 'CustomError';

在ES6中，这很简单:

class CustomError extends Error {}

...and you can detect support for ES6 classes with try {eval('class X{}'), but you'll get a syntax error if you attempt to include the ES6 version in a script that's loaded by older browsers. So the only way to support all browsers would be to load a separate script dynamically (e.g. via AJAX or eval()) for browsers that support ES6. A further complication is that eval() isn't supported in all environments (due to Content Security Policies), which may or may not be a consideration for your project.

所以现在，对于需要支持非es6浏览器的代码来说，无论是上述第一种方法，还是直接使用Error而不尝试扩展它，似乎都是最好的方法。

There is one other approach that some people might want to consider, which is to use Object.setPrototypeOf() where available to create an error object that's an instance of your custom error type but which looks and behaves more like a native error in the console (thanks to Ben's answer for the recommendation). Here's my take on that approach: https://gist.github.com/mbrowne/fe45db61cea7858d11be933a998926a8. But given that one day we'll be able to just use ES6, personally I'm not sure the complexity of that approach is worth it.

这段代码显示了这一切。

function add(x, y) {
      if (x && y) {
        return x + y;
      } else {
        /**
         * 
         * the error thrown will be instanceof Error class and InvalidArgsError also
         */
        throw new InvalidArgsError();
        // throw new Invalid_Args_Error(); 
      }
    }

    // Declare custom error using using Class
    class Invalid_Args_Error extends Error {
      constructor() {
        super("Invalid arguments");
        Error.captureStackTrace(this);
      }
    }

    // Declare custom error using Function
    function InvalidArgsError(message) {
      this.message = `Invalid arguments`;
      Error.captureStackTrace(this);
    }
    // does the same magic as extends keyword
    Object.setPrototypeOf(InvalidArgsError.prototype, Error.prototype);

    try{
      add(2)
    }catch(e){
      // true
      if(e instanceof Error){
        console.log(e)
      }
      // true
      if(e instanceof InvalidArgsError){
        console.log(e)
      }
    }

重要提示:这个答案来自2016年，现在可能已经过时了。JavaScript总体上，特别是Node.js进步了很多，现在提供了更多的语法可能性来实现相同的结果。下面的内容是出于历史原因而保留的，只是为了以防有人正在处理遗留的Node.js版本。

最初的回答:

为了完整起见——因为之前的回答都没有提到这个方法——如果你正在使用Node.js，不必关心浏览器兼容性，那么使用内置的util模块继承(官方文档在这里)就很容易达到预期的效果。

例如，假设你想要创建一个自定义错误类，将错误代码作为第一个参数，错误消息作为第二个参数:

文件custom-error.js:

'use strict';

var util = require('util');

function CustomError(code, message) {
  Error.captureStackTrace(this, CustomError);
  this.name = CustomError.name;
  this.code = code;
  this.message = message;
}

util.inherits(CustomError, Error);

module.exports = CustomError;

现在你可以实例化并传递/抛出你的CustomError:

var CustomError = require('./path/to/custom-error');

// pass as the first argument to your callback
callback(new CustomError(404, 'Not found!'));

// or, if you are working with try/catch, throw it
throw new CustomError(500, 'Server Error!');

注意，对于这个代码片段，堆栈跟踪将具有正确的文件名和行，错误实例将具有正确的名称!

这是由于使用了captureStackTrace方法，该方法在目标对象上创建了一个堆栈属性(在本例中，实例化了CustomError)。有关它如何工作的更多细节，请查看这里的文档。

在Mohsen的回答中指出，在ES6中可以使用类来扩展错误。这要容易得多，而且它们的行为与本机错误更一致……但不幸的是，如果你需要支持前es6版本的浏览器，在浏览器中使用它并不是一件简单的事情。下面是关于如何实施的一些注意事项，但与此同时，我建议一个相对简单的方法，它包含了其他答案中的一些最好的建议:

function CustomError(message) {
    //This is for future compatibility with the ES6 version, which
    //would display a similar message if invoked without the
    //`new` operator.
    if (!(this instanceof CustomError)) {
        throw new TypeError("Constructor 'CustomError' cannot be invoked without 'new'");
    }
    this.message = message;

    //Stack trace in V8
    if (Error.captureStackTrace) {
       Error.captureStackTrace(this, CustomError);
    }
    else this.stack = (new Error).stack;
}
CustomError.prototype = Object.create(Error.prototype);
CustomError.prototype.name = 'CustomError';

在ES6中，这很简单:

class CustomError extends Error {}

...and you can detect support for ES6 classes with try {eval('class X{}'), but you'll get a syntax error if you attempt to include the ES6 version in a script that's loaded by older browsers. So the only way to support all browsers would be to load a separate script dynamically (e.g. via AJAX or eval()) for browsers that support ES6. A further complication is that eval() isn't supported in all environments (due to Content Security Policies), which may or may not be a consideration for your project.

所以现在，对于需要支持非es6浏览器的代码来说，无论是上述第一种方法，还是直接使用Error而不尝试扩展它，似乎都是最好的方法。

There is one other approach that some people might want to consider, which is to use Object.setPrototypeOf() where available to create an error object that's an instance of your custom error type but which looks and behaves more like a native error in the console (thanks to Ben's answer for the recommendation). Here's my take on that approach: https://gist.github.com/mbrowne/fe45db61cea7858d11be933a998926a8. But given that one day we'll be able to just use ES6, personally I'm not sure the complexity of that approach is worth it.

在2018年，我认为这是最好的方式;支持IE9+和现代浏览器。

更新:请参阅此测试和repo以了解不同实现的比较。

function CustomError(message) {
    Object.defineProperty(this, 'name', {
        enumerable: false,
        writable: false,
        value: 'CustomError'
    });

    Object.defineProperty(this, 'message', {
        enumerable: false,
        writable: true,
        value: message
    });

    if (Error.hasOwnProperty('captureStackTrace')) { // V8
        Error.captureStackTrace(this, CustomError);
    } else {
        Object.defineProperty(this, 'stack', {
            enumerable: false,
            writable: false,
            value: (new Error(message)).stack
        });
    }
}

if (typeof Object.setPrototypeOf === 'function') {
    Object.setPrototypeOf(CustomError.prototype, Error.prototype);
} else {
    CustomError.prototype = Object.create(Error.prototype, {
        constructor: { value: CustomError }
    });
}

还要注意__proto__属性已弃用，该属性在其他答案中广泛使用。

我建议的解决方案是使用error的.name属性来区分错误类型，而不是instancof

这并没有完全回答问题，但我认为这是一个合理的解决方案，至少在某些情况下。

我所看到的能够拥有一个instanceof CustomError的好处是，您可以在promise catch处理程序中进行自定义处理。

例如:

class CustomError extends Error {/** ... **/}

axios
  .post(url, payload)
  .then(data => {
    if (!data.loggedIn) throw CustomError("not logged in");
    return data;
  })
  .catch(error => {
    if (error instanceof CustomError) {/** custom handling of error*//}
    throw error
  })

如果这是你想要达到的目的，.name参数也很适合你:

export const ERROR_NOT_LOGGED_IN = "ERROR_NOT_LOGGED_IN";

axios
  .post(url, payload)
  .then(data => {
    if (!data.loggedIn) throw Error("not logged in").name=ERROR_NOT_LOGGED_IN ;
    return data;
  })
  .catch(error => {
    if (error.name === ERROR_NOT_LOGGED_IN) {/** custom handling of error*//}
    throw error
  })