我有一个这样的数据结构:
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'
}, {
'name': 'Part 3B',
'size': '5',
'qty' : '20'
}, {
'name': 'Part 3C',
'size': '7.5',
'qty' : '20'
}
]
};
我想使用这些变量访问数据:
var part1name = "part1.name";
var part2quantity = "part2.qty";
var part3name1 = "part3[0].name";
part1name应该用someObject.part1.name的值填充，即“Part 1”。part2quantity也是一样，它的容量是60。
有没有办法实现这与纯javascript或JQuery?
这是一个有lodash的单班轮。
const deep = { l1: { l2: { l3: "Hello" } } };
const prop = "l1.l2.l3";
const val = _.reduce(prop.split('.'), function(result, value) { return result ? result[value] : undefined; }, deep);
// val === "Hello"
或者更好……
const val = _.get(deep, prop);
或ES6版本w/ reduce…
const val = prop.split('.').reduce((r, val) => { return r ? r[val] : undefined; }, deep);
普伦克尔
这里的解决方案仅用于访问深度嵌套的键。我需要一个来访问、添加、修改和删除密钥。这是我想到的:
var deepAccessObject = function(object, path_to_key, type_of_function, value){
switch(type_of_function){
//Add key/modify key
case 0:
if(path_to_key.length === 1){
if(value)
object[path_to_key[0]] = value;
return object[path_to_key[0]];
}else{
if(object[path_to_key[0]])
return deepAccessObject(object[path_to_key[0]], path_to_key.slice(1), type_of_function, value);
else
object[path_to_key[0]] = {};
}
break;
//delete key
case 1:
if(path_to_key.length === 1){
delete object[path_to_key[0]];
return true;
}else{
if(object[path_to_key[0]])
return deepAccessObject(object[path_to_key[0]], path_to_key.slice(1), type_of_function, value);
else
return false;
}
break;
default:
console.log("Wrong type of function");
}
};
Path_to_key:数组中的路径。你可以用你的string_path.split(".")替换它。
Type_of_function: 0用于访问(不传递任何值给值)，0用于添加和修改。1表示删除。
/**
* Access a deep value inside a object
* Works by passing a path like "foo.bar", also works with nested arrays like "foo[0][1].baz"
* @author Victor B. https://gist.github.com/victornpb/4c7882c1b9d36292308e
* Unit tests: http://jsfiddle.net/Victornpb/0u1qygrh/
*/
function getDeepVal(obj, path) {
if (typeof obj === "undefined" || obj === null) return;
path = path.split(/[\.\[\]\"\']{1,2}/);
for (var i = 0, l = path.length; i < l; i++) {
if (path[i] === "") continue;
obj = obj[path[i]];
if (typeof obj === "undefined" || obj === null) return;
}
return obj;
}
适用于
getDeepVal(obj,'foo.bar')
getDeepVal(obj,'foo.1.bar')
getDeepVal(obj,'foo[0].baz')
getDeepVal(obj,'foo[1][2]')
getDeepVal(obj,"foo['bar'].baz")
getDeepVal(obj,"foo['bar']['baz']")
getDeepVal(obj,"foo.bar.0.baz[1]['2']['w'].aaa[\"f\"].bb")
受到@webjay的回答的启发:
https://stackoverflow.com/a/46008856/4110122
我做了这个函数，你可以用它来获取/设置/取消设置对象中的任何值
function Object_Manager(obj, Path, value, Action)
{
try
{
if(Array.isArray(Path) == false)
{
Path = [Path];
}
let level = 0;
var Return_Value;
Path.reduce((a, b)=>{
level++;
if (level === Path.length)
{
if(Action === 'Set')
{
a[b] = value;
return value;
}
else if(Action === 'Get')
{
Return_Value = a[b];
}
else if(Action === 'Unset')
{
delete a[b];
}
}
else
{
return a[b];
}
}, obj);
return Return_Value;
}
catch(err)
{
console.error(err);
return obj;
}
}
使用它:
// Set
Object_Manager(Obj,[Level1,Level2,Level3],New_Value, 'Set');
// Get
Object_Manager(Obj,[Level1,Level2,Level3],'', 'Get');
// Unset
Object_Manager(Obj,[Level1,Level2,Level3],'', 'Unset');
AngularJS有$scope.$eval
在AngularJS中，我们可以使用$scope。$eval方法访问嵌套对象:
$scope.someObject = someObject;
console.log( $scope.$eval("someObject.part3[0].name") ); //Part 3A
有关更多信息，请参见
AngularJS $scope API引用- $eval
演示
angular.module("app",[])
.run(function($rootScope) {
$rootScope.someObject = {
'part2' : {
'name': 'Part 2',
'size': '15',
'qty' : '60'
},
'part3' : [{
'name': 'Part 3A',
'size': '10',
'qty' : '20'
},{
name: 'Part 3B'
}]
};
console.log(
"part3[0].name =",
$rootScope.$eval("someObject.part3[0].name")
);
})
<script src="//unpkg.com/angular/angular.js"></script>
<body ng-app="app"
</body>
