在 Typescript 中将一个对象映射到另一个对象

Question

我有一个角色对象，我想使用 PrimeNG 将其映射到 TreeNode 对象以在树中显示它。角色对象是这样的（图中也有）

role: [
id: ....
name: ....
   description: ....
   roles[]: .....
]

树节点对象的结构如下：

{
"data": 
[
    {
        "label": "Documents",
        "data": "Documents Folder",
        "expandedIcon": "fa-folder-open",
        "collapsedIcon": "fa-folder",
        "children": [{
                "label": "Work",
                "data": "Work Folder",
                "expandedIcon": "fa-folder-open",
                "collapsedIcon": "fa-folder",
                "children": [{"label": "Expenses.doc", "icon": "fa-file-word-o", "data": "Expenses Document"}, {"label": "Resume.doc", "icon": "fa-file-word-o", "data": "Resume Document"}]
            },
            {
                "label": "Home",
                "data": "Home Folder",
                "expandedIcon": "fa-folder-open",
                "collapsedIcon": "fa-folder",
                "children": [{"label": "Invoices.txt", "icon": "fa-file-word-o", "data": "Invoices for this month"}]
            }]
    },
    {
        "label": "Pictures",
        "data": "Pictures Folder",
        "expandedIcon": "fa-folder-open",
        "collapsedIcon": "fa-folder",
        "children": [
            {"label": "barcelona.jpg", "icon": "fa-file-image-o", "data": "Barcelona Photo"},
            {"label": "logo.jpg", "icon": "fa-file-image-o", "data": "PrimeFaces Logo"},
            {"label": "primeui.png", "icon": "fa-file-image-o", "data": "PrimeUI Logo"}]
    },
    {
        "label": "Movies",
        "data": "Movies Folder",
        "expandedIcon": "fa-folder-open",
        "collapsedIcon": "fa-folder",
        "children": [{
                "label": "Al Pacino",
                "data": "Pacino Movies",
                "children": [{"label": "Scarface", "icon": "fa-file-video-o", "data": "Scarface Movie"}, {"label": "Serpico", "icon": "fa-file-video-o", "data": "Serpico Movie"}]
            },
            {
                "label": "Robert De Niro",
                "data": "De Niro Movies",
                "children": [{"label": "Goodfellas", "icon": "fa-file-video-o", "data": "Goodfellas Movie"}, {"label": "Untouchables", "icon": "fa-file-video-o", "data": "Untouchables Movie"}]
            }]
    }
]

}

 data.roles.forEach((role, index) => {
        //this.roleTree.label = role.Name;
        //this.roleTree.data = role.ID;

        let treeNode: TreeNode = {
            label: role.Name,
            data: role

        }

        this.treeNodes.push(treeNode);
        console.log(role);
        console.log(index);

    });

但是当我尝试'role'中的'roles'映射到treeNode中的'children'时，这段代码似乎太复杂了。我看过一些像这样的例子，但它映射的是相同的字段名称。

我是 Typesript 的新手，是否有一种变通方法可以通过指定要映射到 'label' 角色的字段名（例如名称）来将我的角色对象转换为带有子节点的 treeNode？

非常感谢代码示例。

Answer 1

嗯，我不是 100% 确定您使用的 Role 和 TreeNode 类型。这是我根据您问题中的代码做出的猜测。

Role 有一些您关心的属性，但棘手的是 roles 属性，我猜它应该是 [=13= 的数组] 对象：

interface Role {
  id: string;
  name: string;
  description: string;
  roles: Role[];
}

同样，TreeNode 也有一些属性，但棘手的是 children 属性，它是 TreeNode 对象的数组。另外，我假设 TreeNode 在 data 类型中是通用的，在这种情况下你想做 TreeNode<Role>，意思是 data 属性将是一个 Role 对象：

interface TreeNode<T> {
  label: string;
  data: T;
  expandedIcon?: string;
  collapsedIcon?: string;
  children: TreeNode<T>[];
}

如果这些是正确的，那么你可以使用下面的roleToTreeNode()函数将一个Role对象映射到一个TreeNode<Role>对象：

function roleToTreeNode(role: Role): TreeNode<Role> {
  return {
    label: role.name,
    data: role,
    children: role.roles.map(roleToTreeNode)
  };
}

children: 行是函数的操作部分：您正在获取 role.roles 数组，并将每个 Role 元素映射到 TreeNode<Role>，即roleToTreeNode() 函数的作用。也就是说，roleToTreeNode()是一个调用自身的递归函数。

这有意义吗？希望有所帮助。祝你好运！

在 Typescript 中将一个对象映射到另一个对象

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