Non-iteratable解决方案

主要功能:

var keyByValue = function(value) {

    var kArray = Object.keys(greetings);        // Creating array of keys
    var vArray = Object.values(greetings);      // Creating array of values
    var vIndex = vArray.indexOf(value);         // Finding value index 

    return kArray[vIndex];                      // Returning key by value index
}

对象的键和值:

var greetings = {
    english   : "hello",
    ukranian  : "привіт"
};

测试:

keyByValue("привіт");
// => "ukranian"

function getKeyByValue(object, value) {
  return Object.keys(object).find(key => object[key] === value);
}

ES6，没有原型突变或外部库。

的例子,

函数getKeyByValue(对象，值){ 返回种(对象)。Find (key =>对象[key] === value); ｝ Const map = {"first": "1"， "second": "2"}; console.log (getKeyByValue(地图,“2”));

如果你有一个数组值的对象。这里有一个很好的例子。让我们假设您希望根据所拥有的文件的扩展名显示一个图标。具有相同图标的所有扩展都在相同的对象值下。

注意:将这里的case包装在一个对象中要比使用大量case进行切换要好。

检查下面的代码片段(用es6编写)，看看我们如何为特定的扩展返回特定的键。

我从这个git仓库拿到了扩展名列表

// Oject that contains different icons for different extentions const icons = { "music": ["mp3", "m4a", "ogg", "acc", "flac","m3u", "wav"], "video": ["mp4","webm", "mkv", "avi", "mov", "m4v", "mpeg"], "image": ["jpg", "gif", "png", "jpeg", "tif", "psd", "raw", "ico"], "archives": ["zip", "rar", "tar", "dmg", "jar"], "3d-files": ["3ds", "dwg", "obj", "dae", "skp", "fbx"], "text": ["doc", "rtf", "txt", "odt", "tex"], "vector-graphics":["ai", "svg"], "pdf": ["pdf"], "data": ["xml", "csv", "xls"] } const get_icon_Key =( icons_object,file_extention) => { // For each key we chack if the value is contained in the list of values let key = Object.keys(icons_object).find( k=> icons[k].find( // At this leve we check if the extention exist in the array of the specific object value ie. 'music', 'video' ... icons_ext => icons_ext === file_extention) // if we find it means this is the key we are looking for ? true: false); return key } console.log(`The icon of for mp3 extention is: => ${get_icon_Key(icons,"mp3")}`) console.log(`The icon of for mp4 extention is: => ${get_icon_Key(icons,"mp4")}`)

如果你正在使用下划线或Lodash库，你可以使用_。findKey功能:

var users = {
  'barney':  { 'age': 36, 'active': true },
  'fred':    { 'age': 40, 'active': false },
  'pebbles': { 'age': 1,  'active': true }
};

_.findKey(users, function(o) { return o.age < 40; });
// => 'barney' (iteration order is not guaranteed)

// The `_.matches` iteratee shorthand.
_.findKey(users, { 'age': 1, 'active': true });
// => 'pebbles'

// The `_.matchesProperty` iteratee shorthand.
_.findKey(users, ['active', false]);
// => 'fred'

// The `_.property` iteratee shorthand.
_.findKey(users, 'active');
// => 'barney'

来到这里(2022年)，寻找OP问题的近似变体。变化:

如何根据一个值找到一个对象键，其中键可以保存值的集合?

对于这个用例，从equal(===)切换到.includes():

const foo = ['a', 'b','c'];
const bar = ['x', 'y', 'z'];
const bat = [2, 5, 'z'];
const obj = {foo: foo, bar: bar, bat: bat};

const findMe = (v) => {
  return Object.keys(obj).filter((k) => obj[k].includes(v))
}

findMe('y') // ['bar']
findMe('z') // ['bar', 'bat']

lodash way https://lodash.com/docs#findKey

Var用户= { 'barney':{'年龄':36，'活跃':true}， 'fred': {'age': 40， 'active': false}， '鹅卵石':{'年龄':1，'活动':true} }; _。findKey(users， {'age': 1， 'active': true}); //→'鹅卵石'