这是我使用的解决方案:

function resolve(path, obj=self, separator='.') {
    var properties = Array.isArray(path) ? path : path.split(separator)
    return properties.reduce((prev, curr) => prev?.[curr], obj)
}

使用示例:

// accessing property path on global scope
resolve("document.body.style.width")
// or
resolve("style.width", document.body)

// accessing array indexes
// (someObject has been defined in the question)
resolve("part3.0.size", someObject) // returns '10'

// accessing non-existent properties
// returns undefined when intermediate properties are not defined:
resolve('properties.that.do.not.exist', {hello:'world'})

// accessing properties with unusual keys by changing the separator
var obj = { object: { 'a.property.name.with.periods': 42 } }
resolve('object->a.property.name.with.periods', obj, '->') // returns 42

// accessing properties with unusual keys by passing a property name array
resolve(['object', 'a.property.name.with.periods'], obj) // returns 42

限制:

不能将方括号([])用于数组下标-尽管在分隔符令牌之间指定数组下标(例如，.)可以正常工作，如上所示。

也适用于对象内的数组/数组。 防御无效值。

/** * Retrieve nested item from object/array * @param {Object|Array} obj * @param {String} path dot separated * @param {*} def default value ( if result undefined ) * @returns {*} */ function path(obj, path, def){ var i, len; for(i = 0,path = path.split('.'), len = path.length; i < len; i++){ if(!obj || typeof obj !== 'object') return def; obj = obj[path[i]]; } if(obj === undefined) return def; return obj; } ////////////////////////// // TEST // ////////////////////////// var arr = [true, {'sp ace': true}, true] var obj = { 'sp ace': true, arr: arr, nested: {'dotted.str.ing': true}, arr3: arr } shouldThrow(`path(obj, "arr.0")`); shouldBeDefined(`path(obj, "arr[0]")`); shouldBeEqualToNumber(`path(obj, "arr.length")`, 3); shouldBeTrue(`path(obj, "sp ace")`); shouldBeEqualToString(`path(obj, "none.existed.prop", "fallback")`, "fallback"); shouldBeTrue(`path(obj, "nested['dotted.str.ing'])`); <script src="https://cdn.rawgit.com/coderek/e7b30bac7634a50ad8fd/raw/174b6634c8f57aa8aac0716c5b7b2a7098e03584/js-test.js"></script>

这可能永远都不会曝光……但不管怎样，它在这里。

将[]括号语法替换为。 继续前进。字符 删除空白字符串 找到路径(否则未定义)

(为了找到一个对象的路径，使用这个pathTo解决方案。)

// "one liner" (ES6) const deep_value = (obj, path) => path .replace(/\[|\]\.?/g, '.') .split('.') .filter(s => s) .reduce((acc, val) => acc && acc[val], obj); // ... and that's it. var someObject = { 'part1' : { 'name': 'Part 1', 'size': '20', 'qty' : '50' }, 'part2' : { 'name': 'Part 2', 'size': '15', 'qty' : '60' }, 'part3' : [ { 'name': 'Part 3A', 'size': '10', 'qty' : '20' } // ... ], 'pa[rt3' : [ { 'name': 'Part 3A', 'size': '10', 'qty' : '20' } // ... ] }; console.log(deep_value(someObject, "part1.name")); // Part 1 console.log(deep_value(someObject, "part2.qty")); // 60 console.log(deep_value(someObject, "part3[0].name")); // Part 3A console.log(deep_value(someObject, "part3[0].....name")); // Part 3A - invalid blank paths removed console.log(deep_value(someObject, "pa[rt3[0].name")); // undefined - name does not support square brackets

AngularJS

Speigg的方法非常简洁，尽管我在搜索通过字符串路径访问AngularJS $scope属性的解决方案时发现了这个回复，并进行了一些修改:

$scope.resolve = function( path, obj ) {
    return path.split('.').reduce( function( prev, curr ) {
        return prev[curr];
    }, obj || this );
}

只需要把这个函数放在你的根控制器中，并像这样使用它的任何子范围:

$scope.resolve( 'path.to.any.object.in.scope')

这是我使用的解决方案:

function resolve(path, obj=self, separator='.') {
    var properties = Array.isArray(path) ? path : path.split(separator)
    return properties.reduce((prev, curr) => prev?.[curr], obj)
}

使用示例:

// accessing property path on global scope
resolve("document.body.style.width")
// or
resolve("style.width", document.body)

// accessing array indexes
// (someObject has been defined in the question)
resolve("part3.0.size", someObject) // returns '10'

// accessing non-existent properties
// returns undefined when intermediate properties are not defined:
resolve('properties.that.do.not.exist', {hello:'world'})

// accessing properties with unusual keys by changing the separator
var obj = { object: { 'a.property.name.with.periods': 42 } }
resolve('object->a.property.name.with.periods', obj, '->') // returns 42

// accessing properties with unusual keys by passing a property name array
resolve(['object', 'a.property.name.with.periods'], obj) // returns 42

限制:

不能将方括号([])用于数组下标-尽管在分隔符令牌之间指定数组下标(例如，.)可以正常工作，如上所示。

DotObject = obj => new Proxy(obj， { Get:函数(o,k) { Const m = k.match(/(.+?)\.(.+)/) 返回m ?这一点。Get (o[m[1]]， m[2]): o[k] ｝ }) const test = DotObject({a: {b: {c: 'wow'}}}) console.log(测试[' a.b.c '])