我正在谈论的API在一个非常奇怪的嵌套数组结构中返回它的注册表。我想将这个怪物转换成一个对象，这样我的应用程序就可以轻松访问存储在此输出中的整个对象。
API给我的输出如下所示：
[
[ "settings", "autoLogout", "false" ],
[ "settings", "autoLogoutMinutes", "60" ],
[ "settings", "presets", "true" ],
[ "controller", "rs232", "ip", "192.168.1.11" ],
[ "controller", "rs232", "name", "NX-22" ],
[ "source", "M23836", "slot1", "ip", "192.168.1.30" ]
]
每个数组中的最后一个值表示条目的值，在最后一个条目之前的所有内容都与用于保存值的键相加。由于大小限制，我不能只在那里删除大的json编码对象，所以这不是一个可行的解决方法。
我现在做了一个非常肮脏和缓慢的解决方案，涉及2个eval（）。 （我知道......这是一个禁忌，所以我正在寻找一个更好的解决方案）我猜这可以加载更快，但我无法弄清楚如何......
下面的代码片段使用angular，因为我的应用程序是基于Angular的，但我对任何快速/干净的解决方案持开放态度。一个香草js方法或一些巧妙使用像lodash或下划线的东西将是非常受欢迎的。
我的肮脏和缓慢的解决方案
function DemoCtrl($scope){
$scope.data = [
[ "settings", "autoLogout", "false" ],
[ "settings", "autoLogoutMinutes", "60" ],
[ "settings", "presets", "true" ],
[ "controller", "rs232", "ip", "192.168.1.11" ],
[ "controller", "rs232", "name", "NX-22" ],
[ "source", "M23836", "slot1", "ip", "192.168.1.30" ]
]
$scope.init = function(){
var registry = {};
angular.forEach($scope.data, function(entry){
var keys = '';
entry.forEach(function(value, key, entry){
if( key != entry.length - 1 ){
//not last of array, so must be a key
keys += '[\'' + value + '\']';
// check if the object already exists
if( !angular.isDefined( eval('registry' + keys) ) ){
eval('registry' + keys + ' = {}');
}
}else{
//last one in this entry, must be the value
eval('registry' + keys + ' = \'' + value + '\'');
}
});
});
console.log('registry final');
console.log(registry);
$scope.registry = registry;
}
}<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app>
<div ng-controller="DemoCtrl" ng-init="init()">
<pre>{{ registry | json }}</pre>
</div>
</div>
答案 0 :(得分：4)
这是一个符合您需求的解决方案。另外，请永远不要使用eval。 JavaScript中总有一种更好的方式。
您可以根据自己的使用情况调整以下代码。
var data = [
[ "settings", "autoLogout", "false" ],
[ "settings", "autoLogoutMinutes", "60" ],
[ "settings", "presets", "true" ],
[ "controller", "rs232", "ip", "192.168.1.11" ],
[ "controller", "rs232", "name", "NX-22" ],
[ "source", "M23836", "slot1", "ip", "192.168.1.30" ]
];
var o = {};
data.forEach(function(a) {
var keys = a.slice(0, a.length-2);
var cur = o;
keys.forEach(function(k) {
if (cur[k] == null) {
cur[k] = {};
}
cur = cur[k];
});
cur[a[a.length-2]] = a[a.length-1]
});
output.innerHTML = JSON.stringify(o, null, 2);<pre id='output'></pre>
答案 1 :(得分：2)
一种紧凑的解决方案，可以避免计算数组中的值位置。
var array = [
["settings", "autoLogout", "false"],
["settings", "autoLogoutMinutes", "60"],
["settings", "presets", "true"],
["controller", "rs232", "ip", "192.168.1.11"],
["controller", "rs232", "name", "NX-22"],
["source", "M23836", "slot1", "ip", "192.168.1.30"]
],
obj = {};
array.forEach(function (a) {
var p = obj,
v = a.pop(),
k = a.reduce(function (r, b) {
p[r] = p[r] || {};
p = p[r];
return b;
});
p[k] = v;
});
document.write('<pre>' + JSON.stringify(obj, 0, 4) + '</pre>');
答案 2 :(得分：1)
基本上你只是对它们进行循环并创建嵌套对象。你不需要为此使用eval。你不应该使用它的原因有很多。性能，安全性，可调试性（https://www.nczonline.net/blog/2013/06/25/eval-isnt-evil-just-misunderstood/）
var asObject = {}
//loop over them
data.forEach(function(val) {
//create the top level object that matches the key if it doesn't exist
if (!asObject.hasOwnProperty(val[0])) {
asObject[val[0]] = {};
}
//store it
var theHolder = asObject[val[0]];
//loop over all the middle elements creating nested object
for (var index = 1; index < val.length - 2; index++) {
var element = val[index];
if (!theHolder.hasOwnProperty[element]) {
theHolder[element] = {};
}
theHolder = theHolder[element]
}
//the last one is the value, so just set it
var lastKey = val[val.length - 2];
theHolder[lastKey] = val[val.length - 1];
});
console.log(asObject);
答案 3 :(得分：0)
var someObj = $scope.data.reduce(function(accum, array) {
var value = array.pop(); //pulls last item off of array
//takes the remaining items and condenses them into 1 string
var key = array.reduce(function(acc, str) {
return acc + str;
}, '');
accum[key] = value;
return accum;
}, {}); //the empty object in this line is the seed value
每个子数组都获得处理并传递给空对象种子，然后将其分配给someObj。
答案 4 :(得分：0)
function DemoCtrl($scope){
$scope.data = [
[ "settings", "autoLogout", "false" ],
[ "settings", "autoLogoutMinutes", "60" ],
[ "settings", "presets", "true" ],
[ "controller", "rs232", "ip", "192.168.1.11" ],
[ "controller", "rs232", "name", "NX-22" ],
[ "source", "M23836", "slot1", "ip", "192.168.1.30" ]
]
$scope.init = function(){
var registry = {};
angular.forEach($scope.data, function(entry) {
var len = entry.length, tmp = registry;
for (var i = 0; i < len - 1; i++) {
key = entry[i];
if (i < len - 2) {
if (!tmp[key]) {
tmp[key] = { };
}
tmp = tmp[key];
} else {
tmp[key] = entry[i + 1];
}
}
});
console.log('registry final');
$scope.registry = registry;
}
}<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app>
<div ng-controller="DemoCtrl" ng-init="init()">
{{ registry }}
</div>
</div>
答案 5 :(得分：0)
这是使用递归完成的：
$scope.registry = $scope.data.reduce(function register(registry, entry) {
var key = entry[0];
if (entry.length === 2) {
registry[key] = entry[1];
} else {
registry[key] = register(registry[key] || {}, entry.slice(1));
}
return registry;
}, {});
答案 6 :(得分：0)
以下是基于@Jared Smith的解决方案的另一种选择。在他的解决方案中，键被嵌入到浅地图中的字符串键中。这将创建我的其他解决方案的嵌套对象结构。
如果您是array.reduce（）的新手，请参阅https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/Reduce
var someObj = array.reduce(function(previousVal, currentVal) {
//strip off the value to use at the end
var value = currentVal.pop();
//create all the nested objects
currentVal.reduce(function(acc, str, idx, arr) {
if (idx !== arr.length - 1 ) {
if (!acc.hasOwnProperty(str)) {
acc[str] = {};
}
return acc[str];
} else {
//the last one in the array is the key for the value
acc[str] = value;
return;
}
}, previousVal);
return previousVal;
}, {});
console.log(someObj);