我的观点是:

function objFilter(obj, filter, nonstrict){
  r = {}
  if (!filter) return {}
  if (typeof filter == 'string') return {[filter]: obj[filter]}
  for (p in obj) {
    if (typeof filter == 'object' &&  nonstrict && obj[p] ==  filter[p]) r[p] = obj[p]
    else if (typeof filter == 'object' && !nonstrict && obj[p] === filter[p]) r[p] = obj[p]
    else if (typeof filter == 'function'){ if (filter(obj[p],p,obj)) r[p] = obj[p]}
    else if (filter.length && filter.includes(p)) r[p] = obj[p]
  }
  return r
}

测试用例:

obj = {a:1, b:2, c:3}

objFilter(obj, 'a') // returns: {a: 1}
objFilter(obj, ['a','b']) // returns: {a: 1, b: 2}
objFilter(obj, {a:1}) // returns: {a: 1}
objFilter(obj, {'a':'1'}, true) // returns: {a: 1}
objFilter(obj, (v,k,o) => v%2===1) // returns: {a: 1, c: 3}

https://gist.github.com/bernardoadc/872d5a174108823159d845cc5baba337

永远不要扩展Object.prototype。

可怕的事情会发生在你的代码中。东西会碎的。您正在扩展所有对象类型，包括对象字面量。

这里有一个你可以尝试的简单例子:

    // Extend Object.prototype
Object.prototype.extended = "I'm everywhere!";

    // See the result
alert( {}.extended );          // "I'm everywhere!"
alert( [].extended );          // "I'm everywhere!"
alert( new Date().extended );  // "I'm everywhere!"
alert( 3..extended );          // "I'm everywhere!"
alert( true.extended );        // "I'm everywhere!"
alert( "here?".extended );     // "I'm everywhere!"

而是创建一个传递给对象的函数。

Object.filter = function( obj, predicate) {
    let result = {}, key;

    for (key in obj) {
        if (obj.hasOwnProperty(key) && !predicate(obj[key])) {
            result[key] = obj[key];
        }
    }

    return result;
};

如果你不需要原始对象，这是一个简单的，非常无聊的答案，不浪费内存:

const obj = {'a': 'want this', 'b': 'want this too', 'x': 'remove this'}
const keep = new Set(['a', 'b', 'c'])

function filterObject(obj, keep) {
  Object.keys(obj).forEach(key => {
    if (!keep.has(key)) {
      delete obj[key]
    }
  })
}

如果只过滤少量对象，并且对象没有很多键，则可能不想构造Set，在这种情况下使用数组。Includes而不是set.has。

    var foo = {
    bar: "Yes",
    pipe: "No"
};

const ret =  Object.entries(foo).filter(([key, value])=> value === 'Yes');

https://masteringjs.io/tutorials/fundamentals/filter-object

鉴于

object = {firstname: 'abd', lastname:'tm', age:16, school:'insat'};

keys = ['firstname', 'age'];

然后:

keys.reduce((result, key) => ({ ...result, [key]: object[key] }), {});
// {firstname:'abd', age: 16}

/ /帮助 函数过滤器(对象，…键){ 返回键。Reduce ((result, key) =>({…结果，[key]:对象[key]})， {}); }; / /实例 Const person ={名:' abd'，姓:'tm'，年龄:16岁，学校:'insat'}; //期望只选择名字和年龄键 console.log ( Filter (person， 'firstname'， 'age') ）

如何:

function filterObj(keys, obj) {
  const newObj = {};
  for (let key in obj) {
    if (keys.includes(key)) {
      newObj[key] = obj[key];
    }
  }
  return newObj;
}

还是……

function filterObj(keys, obj) {
  const newObj = {};
  Object.keys(obj).forEach(key => {
    if (keys.includes(key)) {
      newObj[key] = obj[key];
    }
  });
  return newObj;
}