javascript - 从需要的文件扩展 Node.js 中的 Array.prototype

Question

我将以下内容保存在 test.js 中。它在浏览器中成功扩展了 Array，但它似乎不适用于 node 和 require。有人可以解释这里出了什么问题吗？

(function() {

Array.prototype.max = function() {
  return console.log("Array.prototype.max");
};
return Array.max = function() {
  return console.log("Array.max");
};

}).call(this);

然后，从终端:

> My-MacBook-Pro: me$ node
> var test = require("./test")
> [1,2,3].max()
TypeError: Object 1,2,3 has no method 'max'
    at [object Context]:1:9
    at Interface.<anonymous> (repl.js:171:22)
    at Interface.emit (events.js:64:17)
    at Interface._onLine (readline.js:153:10)
    at Interface._line (readline.js:408:8)
    at Interface._ttyWrite (readline.js:585:14)
    at ReadStream.<anonymous> (readline.js:73:12)
    at ReadStream.emit (events.js:81:20)
    at ReadStream._emitKey (tty_posix.js:307:10)
    at ReadStream.onData (tty_posix.js:70:12)
> Array.max()
TypeError: Object function Array() { [native code] } has no method 'max'
    at [object Context]:1:7
    at Interface.<anonymous> (repl.js:171:22)
    at Interface.emit (events.js:64:17)
    at Interface._onLine (readline.js:153:10)
    at Interface._line (readline.js:408:8)
    at Interface._ttyWrite (readline.js:585:14)
    at ReadStream.<anonymous> (readline.js:73:12)
    at ReadStream.emit (events.js:81:20)
    at ReadStream._emitKey (tty_posix.js:307:10)
    at ReadStream.onData (tty_posix.js:70:12)

Answer 1

您可以创建一个包含您的扩展的文件:

数组.extensions.js

if(!Array.prototype.Last){
    Array.prototype.Last = function(){
        return this.slice(-1)[0];
    }
}

if(!Array.prototype.First){
    Array.prototype.First = function(){
        return this[0];
    }
}

然后将此文件包含到您的启动文件中。

应用程序.js:

require('{path}/array.extensions');
var express = require('express');
/* rest of your code */

在启动时引用一次这个文件就足以使用...