Question

我有2个不同的对象数组，我想根据“id”值合并。

所以如果我的第一个数组看起来像这样：

Sub searchfilter(ByVal mytextbox As TextBox, ByVal myfield As String)
    If Not source1.DataSource = ExcelDB.DataSource Then
        source1.DataSource = ExcelDB.DataSource
    End If
    ExcelDB.DataSource = source1
    Dim searchstring As String = ""
    If mytextbox.Text = "" Then
        source1.RemoveFilter()
    Else
        source1.Filter = myfield & " = '" & mytextbox.Text & "'"
        addquery(myfield & "= '" & mytextbox.Text & "'")
    End If
End Sub

我的第二个看起来像这样：

[
  {
   "id": "75318408571184",
   "component": "textInput",
   "index": 0,
   "label": "Text",
   "description": "description",
   "placeholder": "placeholder",
   },
  {
  "id": "9463537670672",
  "component": "textArea",
  "index": 1,
  "label": "Paragraph",
  "description": "description",
  "placeholder": "placeholder"
  }

我想得到这个对象数组：

[
  {
   "id": "75318408571184",
   "value": "value1"
   },
  {
  "id": "9463537670672",
  "value": "value2"
  }

有没有一种巧妙的方法可以在角度或javascript中执行此操作而不循环遍历数组？

Answer 1

试试这个：

var result = firstArray.map(function(item) {
    var second = secondArray.find(function(i) {
        return item.id === i.id;
    });
    return second ? Object.assign(item, second) : item;
});
console.log(result);

Array.prototype.map()在firstArray的每个项目的参数中应用函数，并返回带有修改值的新数组。

Object.assign()是一个函数，它将second对象的属性复制到上面代码中的item对象。

Answer 2

在普通的Javascript中，您可以使用Array.prototype.forEach()和Array.prototype.some()

var obj1 = [{ "id": "75318408571184", "component": "textInput", "index": 0, "label": "Text", "description": "description", "placeholder": "placeholder", }, { "id": "9463537670672", "component": "textArea", "index": 1, "label": "Paragraph", "description": "description", "placeholder": "placeholder" }],
    obj2 = [{ "id": "75318408571184", "value": "value1" }, { "id": "9463537670672", "value": "value2" }];

obj2.forEach(function (a) {
    obj1.some(function (b) {
        if (a.id === b.id) {
            b.value = a.value;
            return true;
        }
    });
});
document.write('<pre>' + JSON.stringify(obj1, 0, 4) + '</pre>');

另一种可能性是首先构建哈希表temp，然后直接操作该项。

var obj1 = [{ "id": "75318408571184", "component": "textInput", "index": 0, "label": "Text", "description": "description", "placeholder": "placeholder", }, { "id": "9463537670672", "component": "textArea", "index": 1, "label": "Paragraph", "description": "description", "placeholder": "placeholder" }],
    obj2 = [{ "id": "75318408571184", "value": "value1" }, { "id": "9463537670672", "value": "value2" }],
    temp = {};

obj1.forEach(function (a, i) {
    temp[a.id] = i;
});
obj2.forEach(function (a) {
    obj1[temp[a.id]].value = a.value;
});
document.write('<pre>' + JSON.stringify(obj1, 0, 4) + '</pre>');

Answer 3

以上答案已经很好了。但是如果你想看看其他一些库，你可以看看这个。 loadash merge

var object = {
  'fruits': ['apple'],
  'vegetables': ['beet']
};

var other = {
 'fruits': ['banana'],
 'vegetables': ['carrot']
};

_.merge(object, other, function(a, b) {
  if (_.isArray(a)) {
    return a.concat(b);
 }
});

// → { 'fruits': ['apple', 'banana'], 'vegetables': ['beet', 'carrot'] }

angularjs按属性值组合2个对象

3 个答案: