相关疑难解决方法(0)

在这段代码中,我创建了一个名为someFunction的函数.然后我修改了Function.prototype.apply并调用方法.因此,我正在运行我的拦截代码(显示警报),而不是我的功能代码正在工作.但是"呼叫"和"应用"都不会拦截直接方法调用.是否有可能拦截这个？

Function.prototype.call = function(){alert("call");};
Function.prototype.apply = function(){alert("apply");};
function someFunction(){}
window.onload = function(){
    someFunction.call(this); //call alert is shown
    someFunction.apply(this); //apply alert is shown
    someFunction(); //how can I intercept this?
}

我有一个类,我想应用代理,观察方法调用和构造函数调用:

Calculator.js

class Calc {
  constructor(){}

  add(a, b) {
    return a+b;
  }

  minus(a, b) {
    return a-b;
  }
}

module.exports = Calc;

index.js

const Calculator = require('./src/Calculator');

const CalculatorLogger = {
  construct: function(target, args, newTarget) {
      console.log('Object instantiated');
      return new target(...args);
  },
  apply: function(target, thisArg, argumentsList) {
      console.log('Method called');
  }
}
const LoggedCalculator = new Proxy(Calculator, CalculatorLogger);
const calculator = new LoggedCalculator();
console.log(calculator.add(1,2));

当调用它时,我希望输出为:

对象实例化

方法叫做

但是,apply没有被调用,我认为这是因为我将Proxy附加到Calculator类,而不是实例化的对象,所以不知道apply陷阱.

如何在方法调用和构造函数调用上构建一个包含所有代理的"观察"代理.

我有以下代码，其中我使用代理对象（代理）来尝试捕获方法调用和属性访问：

示例： https: //jsfiddle.net/r8j4fzxL/2/

(function() {
    'use strict';
    console.clear();

    //some empty class where I want to trap methods props
    class X {
        //...
    }

    let proxy = {
        get: function(target, prop, receiver) {

            console.log('get called: ',
                'target:', target,
                'prop:', prop,
                'receiver:', receiver
            );
            //this is OK, if we are called as a method.
            //but it isn't when called as .prop - because, obviously, we return a function here.
            return function(...args) {
                console.log('wrapper args:', args);
                return 42;
            }
        },


    };


    let …