List-to-tree NPM

list-to-tree

This lib is help-tool for convertation list to tree a data structure.

Attention

Recently I have rewritten the project and now it is based on IronTree - it allowed to do the project in unix way style and added flexibility. IronTree has a fairly rich interface.
The tree can now be sorted - you only need to pass your sorting method if you are not satisfied with the native sorting.

Install on npm

npm install list-to-tree --save

Usage

    var LTT = require('list-to-tree');
    var list = [
    {
        id: 1,
        parent: 0
    }, {
        id: 2,
        parent: 1
    }, {
        id: 3,
        parent: 1
    }, {
        id: 4,
        parent: 2
    }, {
        id: 5,
        parent: 2
    }, {
        id: 6,
        parent: 0
    }, {
        id: 7,
        parent: 0
    }, {
        id: 8,
        parent: 7
    }, {
        id: 9,
        parent: 8
    }, {
        id: 10,
        parent: 0
    }
    ];

    var ltt = new LTT(list, {
        key_id: 'id',
        key_parent: 'parent'
    });
    var tree = ltt.GetTree();

    console.log( tree );

Result

[{
    "id": 1,
    "parent": 0,
    "child": [
        {
            "id": 2,
            "parent": 1,
            "child": [
                {
                    "id": 4,
                    "parent": 2
                }, {
                    "id": 5,
                    "parent": 2
                }
            ]
        },
        {
            "id": 3,
            "parent": 1
        }
    ]
}, {
    "id": 6,
    "parent": 0
}, {
    "id": 7,
    "parent": 0,
    "child": [
        {
            "id": 8,
            "parent": 7,
            "child": [
                {
                    "id": 9,
                    "parent": 8
                }
            ]
        }
    ]
}, {
    "id": 10,
    "parent": 0
}];

Properties

tree - This property is IronTree type and have methods: add, remove, contains, sort, move, traversal, toJson, etc...
options
- key_id (string) Field name for id item. Default: 'id'.
- key_parent (string) Field name for parent id. Default: 'parent'.
- key_child (string) Field name for children of item. Default 'child'.
- empty_children (boolean) Flag for allow empty children property in item. Default: false.

Methods

constructor(list, options)
- params:
  - list - array list with elements. Like { id: 5: parent: 1 }.
  - options - optional parameter. Object for describe flags and field names for tree.
.GetTree() This method will be return json tree
- example:
```
  tree.GetTree()
```

.sort(callback) The custom sort method

callback(a, b) - a and b have IronTree\Node type and have methods: add, remove, get, set, sort, traversal, etc...

example:

function compareById(vector) {
  return (a, b) => {
    const aid = Number(a.get('id'));
    const bid = Number(b.get('id'));
    if (aid > bid) {
      return vector ? 1 : -1;
    } else if (aid < bid) {
      return vector ? -1 : 1;
    } else {
      return 0
    }
  };
}
ltt.sort(compareById(false));