Question

我正在尝试转换此结构：

var initial = [ 
{ Phase: "Phase 1", Step: "Step 1", Task: "Task 1", Value: "5" },
{ Phase: "Phase 1", Step: "Step 1", Task: "Task 2", Value: "10" },
{ Phase: "Phase 1", Step: "Step 2", Task: "Task 1", Value: "15" },
{ Phase: "Phase 1", Step: "Step 2", Task: "Task 2", Value: "20" },
{ Phase: "Phase 2", Step: "Step 1", Task: "Task 1", Value: "25" },
{ Phase: "Phase 2", Step: "Step 1", Task: "Task 2", Value: "30" },
{ Phase: "Phase 2", Step: "Step 2", Task: "Task 1", Value: "35" },
{ Phase: "Phase 2", Step: "Step 2", Task: "Task 2", Value: "40" }
];

到这一个：

var example = {
"Phase 1": {
    "Step 1": {
        "Task 1": { Phase: "Phase 1", Step: "Step 1", Task: "Task 1", Value: "5" }, 
        "Task 2": { Phase: "Phase 1", Step: "Step 1", Task: "Task 2", Value: "10" }
    } ,
    "Step 2": {
        "Task 1": { Phase: "Phase 1", Step: "Step 2", Task: "Task 1", Value: "15" }, 
        "Task 2": { Phase: "Phase 1", Step: "Step 2", Task: "Task 2", Value: "20" }
    }
} ,
"Phase 2": {        
    "Step 1": {
        "Task 1": { Phase: "Phase 2", Step: "Step 1", Task: "Task 1", Value: "25" }, 
        "Task 2": { Phase: "Phase 2", Step: "Step 1", Task: "Task 2", Value: "30" },
    } ,
    "Step 2": {
        "Task 1": { Phase: "Phase 2", Step: "Step 2", Task: "Task 1", Value: "35" }, 
        "Task 2": { Phase: "Phase 2", Step: "Step 2", Task: "Task 2", Value: "40" }     
    }
}
};

所以我可以轻松提取像example['Phase 2']['Step 1']['Task 1']['Value']

这样的值

我使用像这样的groupBy函数完成了第一步：

function groupBy(d, arr) {
return arr.reduce(function(acc, i) {
    var p = i[d];
    var temp = acc[p] || [];
    temp.push(i);
    acc[p] = temp;
    return acc;
}, {})
}

所以我做var groupedByPhase = groupBy('Phase', initial); 我得到groupedByPhase：

{
"Phase 1" : [
{ Phase: "Phase 1", Step: "Step 1", Task: "Task 1", Value: "5" },
{ Phase: "Phase 1", Step: "Step 1", Task: "Task 2", Value: "10" },
{ Phase: "Phase 1", Step: "Step 2", Task: "Task 1", Value: "15" },
{ Phase: "Phase 1", Step: "Step 2", Task: "Task 2", Value: "20" },
],
"Phase 2": [
{ Phase: "Phase 2", Step: "Step 1", Task: "Task 1", Value: "25" },
{ Phase: "Phase 2", Step: "Step 1", Task: "Task 2", Value: "30" },
{ Phase: "Phase 2", Step: "Step 2", Task: "Task 1", Value: "35" },
{ Phase: "Phase 2", Step: "Step 2", Task: "Task 2", Value: "40" }
] 
}

我还设法使用此功能分组：

function groupByInNestedObj(item, obj) {
var x = {};
for (var i in obj) {
    x[i] = groupBy(item, obj[i]);
}
return x;
}

可以在调用groupByInNestedObj('Step', groupBy('Phase', initial))

时获取

 {
"Phase 1" : {
    "Step 1": [
    { Phase: "Phase 1", Step: "Step 1", Task: "Task 1", Value: "5" },
    { Phase: "Phase 1", Step: "Step 1", Task: "Task 2", Value: "10" }],
    "Step 2": [
    { Phase: "Phase 1", Step: "Step 2", Task: "Task 1", Value: "15" },
    { Phase: "Phase 1", Step: "Step 2", Task: "Task 2", Value: "20" },
    ]},
"Phase 2": {
    "Step 1:" [
    { Phase: "Phase 2", Step: "Step 1", Task: "Task 1", Value: "25" },
    { Phase: "Phase 2", Step: "Step 1", Task: "Task 2", Value: "30" }],
    "Step 2:"[
    { Phase: "Phase 2", Step: "Step 2", Task: "Task 1", Value: "35" },
    { Phase: "Phase 2", Step: "Step 2", Task: "Task 2", Value: "40" }
    ]}
}

但是我有点卡在这里，做下一个。理想情况下，我希望能够groupBy("Task", groupBy("Step", groupBy("Phase", initial)))，以便groupBy在树的最深层进行分组。欢迎任何建议！

注意：我确实尝试过第二步来实现这个功能

function groupByInNestedObj2 (item, obj) {
    var x = {};
    for(var i in obj) {
        for (var j in obj[i]) {
            x[i][j] = groupBy(item, obj[i][j]);
        }
    }
    return x;
}

但它似乎不起作用。

注意2：上一个函数的第二个版本有效，但不纯，因为它修改了通过它的对象

function groupByInNestedObj2 (item, obj) {
    var x = {};
    for(var i in obj) {
        x[i] = obj[i]
        for (var j in x[i]) {
            x[i][j] = groupBy('Task', x[i][j]);
        }
    }
    return x;
}

所以当我做var groupByPhaseAndStepAndTask = groupByInNestedObj2('Task', groupByPhaseAndStep) groupByPhaseAndStep也被修改，这是一个不良的副作用。仍在努力。

Answer 1

您可以尝试使用.reduce并检查是否存在对象，例如

＆＃13;

var initial = [ 
  { Phase: "Phase 1", Step: "Step 1", Task: "Task 1", Value: "5" },
  { Phase: "Phase 1", Step: "Step 1", Task: "Task 2", Value: "10" },
  { Phase: "Phase 1", Step: "Step 2", Task: "Task 1", Value: "15" },
  { Phase: "Phase 1", Step: "Step 2", Task: "Task 2", Value: "20" },
  { Phase: "Phase 2", Step: "Step 1", Task: "Task 1", Value: "25" },
  { Phase: "Phase 2", Step: "Step 1", Task: "Task 2", Value: "30" },
  { Phase: "Phase 2", Step: "Step 2", Task: "Task 1", Value: "35" },
  { Phase: "Phase 2", Step: "Step 2", Task: "Task 2", Value: "40" }
];

var result = initial.reduce(function (prev, current) {
  prev[current.Phase] = prev[current.Phase] || {};
  prev[current.Phase][current.Step] = prev[current.Phase][current.Step] || {};
  prev[current.Phase][current.Step][current.Task] = current;
  return prev;
}, {});

console.log(JSON.stringify(result, null, 2));

＆＃13;

Answer 2

我们可以通过一个for循环来实现这一点：

var initial = [ 
{ Phase: "Phase 1", Step: "Step 1", Task: "Task 1", Value: "5" },
{ Phase: "Phase 1", Step: "Step 1", Task: "Task 2", Value: "10" },
{ Phase: "Phase 1", Step: "Step 2", Task: "Task 1", Value: "15" },
{ Phase: "Phase 1", Step: "Step 2", Task: "Task 2", Value: "20" },
{ Phase: "Phase 2", Step: "Step 1", Task: "Task 1", Value: "25" },
{ Phase: "Phase 2", Step: "Step 1", Task: "Task 2", Value: "30" },
{ Phase: "Phase 2", Step: "Step 2", Task: "Task 1", Value: "35" },
{ Phase: "Phase 2", Step: "Step 2", Task: "Task 2", Value: "40" }
];
var final = {}
initial.forEach(function(d){
  if (!final[d.Phase]) //phase not present so make an object
  	final[d.Phase] = {};
  if (!final[d.Phase][d.Step]) //step not present so make an object
  	final[d.Phase][d.Step] = {};
  if (!final[d.Phase][d.Step][d.Task])//task not present so make an object and store the object
  	final[d.Phase][d.Step][d.Task] = d;
  
})
console.log(final)

Answer 3

使用lodash和answer的更通用的方式：

＆＃13;

var initial = [
  { Phase: "Phase 1", Step: "Step 1", Task: "Task 1", Value: "5" },
  { Phase: "Phase 1", Step: "Step 1", Task: "Task 2", Value: "10" },
  { Phase: "Phase 1", Step: "Step 2", Task: "Task 1", Value: "15" },
  { Phase: "Phase 1", Step: "Step 2", Task: "Task 2", Value: "20" },
  { Phase: "Phase 2", Step: "Step 1", Task: "Task 1", Value: "25" },
  { Phase: "Phase 2", Step: "Step 1", Task: "Task 2", Value: "30" },
  { Phase: "Phase 2", Step: "Step 2", Task: "Task 1", Value: "35" },
  { Phase: "Phase 2", Step: "Step 2", Task: "Task 2", Value: "40" }
];

_.mixin({
  groupByMulti: function(obj, values, context) {
    if (!values.length) return obj;
    var byFirst = _.groupBy(obj, _.head(values), context);
    for (var prop in byFirst) {
      byFirst[prop] = _.groupByMulti(byFirst[prop], _.tail(values), context);
    }
    return byFirst;
  }
});

var tree = _(initial).groupByMulti(['Phase', 'Step', 'Task']);
$('#pre').append(JSON.stringify(tree, null, 3));

＆＃13;

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.0.0/lodash.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<pre id='pre'></pre>

＆＃13;

Javascript将对象数组转换为树

3 个答案: