var find = function(root, path) {
  var segments = path.split('.'),
      cursor = root,
      target;

  for (var i = 0; i < segments.length; ++i) {
   target = cursor[segments[i]];
   if (typeof target == "undefined") return void 0;
   cursor = target;
  }

  return cursor;
};

var obj = { a: { b: '1', c: '2' } }
find(obj, "a.b"); // 1

var set = function (root, path, value) {
   var segments = path.split('.'),
       cursor = root,
       target;

   for (var i = 0; i < segments.length - 1; ++i) {
      cursor = cursor[segments[i]] || { };
   }

   cursor[segments[segments.length - 1]] = value;
};

set(obj, "a.k", function () { console.log("hello world"); });

find(obj, "a.k")(); // hello world

使用对象扫描似乎有点过度，但您可以简单地这样做

// const objectScan = require('object-scan'); const get = (obj, p) => objectScan([p]， {abort: true, rtn: 'value'})(obj); Const obj = {a: {b: '1'， c: '2'}}; console.log (get (obj, ' a.b ')); // => console.log (get (obj, * . c)); // => .as-console-wrapper {max-height: 100% !重要;上图:0} < script src = " https://bundle.run/object-scan@13.7.1 " > < /脚本>

声明:我是object-scan的作者

自述中有很多更高级的例子。

其他的建议有点晦涩难懂，所以我想我应该贡献一下:

Object.prop = function(obj, prop, val){
    var props = prop.split('.')
      , final = props.pop(), p 
    while(p = props.shift()){
        if (typeof obj[p] === 'undefined')
            return undefined;
        obj = obj[p]
    }
    return val ? (obj[final] = val) : obj[final]
}

var obj = { a: { b: '1', c: '2' } }

// get
console.log(Object.prop(obj, 'a.c')) // -> 2
// set
Object.prop(obj, 'a.c', function(){})
console.log(obj) // -> { a: { b: '1', c: [Function] } }

如果您希望以尽可能快的方式做到这一点，同时处理与路径解析或属性解析有关的任何问题，请检查path-value。

const {resolveValue} = require('path-value');

const value = resolveValue(obj, 'a.b.c');

该库是100%的TypeScript，适用于NodeJS +所有web浏览器。它是完全可扩展的，你可以使用较低级别的resolvePath，如果你愿意，你可以用自己的方式处理错误。

const {resolvePath} = require('path-value');

const res = resolvePath(obj, 'a.b.c'); //=> low-level parsing result descriptor

这是ninjagecko提出的我的扩展方案。

对我来说，简单的字符串表示法是不够的，所以下面的版本支持如下内容:

index(obj, 'data.accounts[0].address[0].postcode');

/**
 * Get object by index
 * @supported
 * - arrays supported
 * - array indexes supported
 * @not-supported
 * - multiple arrays
 * @issues:
 *  index(myAccount, 'accounts[0].address[0].id') - works fine
 *  index(myAccount, 'accounts[].address[0].id') - doesnt work
 * @Example:
 * index(obj, 'data.accounts[].id') => returns array of id's
 * index(obj, 'data.accounts[0].id') => returns id of 0 element from array
 * index(obj, 'data.accounts[0].addresses.list[0].id') => error
 * @param obj
 * @param path
 * @returns {any}
 */
var index = function(obj, path, isArray?, arrIndex?){

    // is an array
    if(typeof isArray === 'undefined') isArray = false;
    // array index,
    // if null, will take all indexes
    if(typeof arrIndex === 'undefined') arrIndex = null;

    var _arrIndex = null;

    var reduceArrayTag = function(i, subArrIndex){
        return i.replace(/(\[)([\d]{0,})(\])/, (i) => {
            var tmp = i.match(/(\[)([\d]{0,})(\])/);
            isArray = true;
            if(subArrIndex){
                _arrIndex =  (tmp[2] !== '') ? tmp[2] : null;
            }else{
                arrIndex =  (tmp[2] !== '') ? tmp[2] : null;
            }
            return '';
        });
    }

    function byIndex(obj, i) {
        // if is an array
        if(isArray){
            isArray = false;
            i = reduceArrayTag(i, true);
            // if array index is null,
            // return an array of with values from every index
            if(!arrIndex){
                var arrValues = [];
                _.forEach(obj, (el) => {
                    arrValues.push(index(el, i, isArray, arrIndex));
                })
                return arrValues;
            }
            // if array index is specified
            var value = obj[arrIndex][i];
            if(isArray){
                arrIndex = _arrIndex;
            }else{
                arrIndex = null;
            }
            return value;
        }else{
            // remove [] from notation,
            // if [] has been removed, check the index of array
            i = reduceArrayTag(i, false);
            return obj[i]
        }
    }

    // reduce with the byIndex method
    return path.split('.').reduce(byIndex, obj)
}

使用数组缩减函数将获得/设置基于提供的路径。

我用a.b.c和a.b.2.c {a:{b:[0,1，{c:7}]}}测试了它，它既可以获取键，也可以将对象更改为设置值

function setOrGet(obj, path=[], newValue){ const l = typeof path === 'string' ? path.split('.') : path; return l.reduce((carry,item, idx)=>{ const leaf = carry[item]; // is this last item in path ? cool lets set/get value if( l.length-idx===1) { // mutate object if newValue is set; carry[item] = newValue===undefined ? leaf : newValue; // return value if its a get/object if it was a set return newValue===undefined ? leaf : obj ; } carry[item] = leaf || {}; // mutate if key not an object; return carry[item]; // return object ref: to continue reduction; }, obj) } console.log( setOrGet({a: {b:1}},'a.b') === 1 || 'Test Case: Direct read failed' ) console.log( setOrGet({a: {b:1}},'a.c',22).a.c===22 || 'Test Case: Direct set failed' ) console.log( setOrGet({a: {b:[1,2]}},'a.b.1',22).a.b[1]===22 || 'Test Case: Direct set on array failed' ) console.log( setOrGet({a: {b:{c: {e:1} }}},'a.b.c.e',22).a.b.c. e===22 || 'Test Case: deep get failed' ) // failed !. Thats your homework :) console.log( setOrGet({a: {b:{c: {e:[1,2,3,4,5]} }}},'a.b.c.e.3 ',22) )

我个人的建议。

除非没有别的办法，否则不要用这种东西!

我看到很多例子，人们用它来翻译json;你会看到locale('app。主页。欢迎')这样的函数。这太糟糕了。如果你已经在object/json中有数据;你知道路径。然后直接使用locale().app.首页示例。欢迎通过改变你的函数返回对象，你得到类型安全，自动完成，不容易出现错别字。