Cloning a JS TreeModel tree

人盡茶涼 提交于 2020-01-13 10:09:53

问题


I need to clone a tree I made using TreeModel.js. What I exactly need to do is duplicating it, make changes to it and check if the number of nodes decreased. If it did, revert to the original tree. Here's a small example of what I do so far to duplicate it, which is not correct:

var tree = new TreeModel();
var root = tree.parse({
    id: 0,
    name: "Root",
    children: [{id: 1, name: "1", children: []},{id: 2, name: "2", children: []}]
});

console.log(root)
var dup = tree.parse(root)
console.log(dup)

Here's a Fiddle. You'll see the difference between the trees by looking at the console:

Node {config: Object, model: Object, children: Array[2], isRoot: function, hasChildren: function…}
Node {config: Object, model: Node, children: Array[2], isRoot: function, hasChildren: function…}

Is there any way to properly clone such a structure? I looked for cloning JS object but still, I can't find a way for cloning this object exactly (such as the prototypes of properties like the model...)


回答1:


You can deep clone the model of the first tree and parse it again to get a second tree.

Taking on your example:

function deepCopy(obj) {
    // You can also use the jquery extend method here
    return JSON.parse(JSON.stringify(obj));
}

var dup = tree.parse(deepCopy(root.model));

Important: If you do not deep clone the model, and just parse it again, you'll end up with the same underlying model shared by both trees which will certainly cause inconsistencies.




回答2:


I finally came to a solution that may help anyone with the same problem:

var tree = new TreeModel();
var root = tree.parse({
    id: 0,
    name: "Root",
    children: [{id: 1, name: "1", children: []},{id: 2, name: "2", children: []}]
});

console.log(root)
var dup = tree.parse(root.model)
console.log(dup)

The parse function takes a model as parameter and the model of root seems to work fine.

EDIT: this solution may bring inconsistencies since the 2 trees are based on the same model. JNS's solution is more appropriate.




回答3:


Why not trying a jQuery deep copy?

var dup = jQuery.extend(true, {}, tree)

I tried your fiddle but it doesn't seem to work.




回答4:


https://github.com/mrluc/owl-deepcopy this worked for me.

newTree = deepCopy(tree)



来源:https://stackoverflow.com/questions/27481417/cloning-a-js-treemodel-tree

易学教程内所有资源均来自网络或用户发布的内容,如有违反法律规定的内容欢迎反馈
该文章没有解决你所遇到的问题?点击提问,说说你的问题,让更多的人一起探讨吧!