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iterates over all items of a tree collection

forEach(callback: DataCallback<T>, parentID?: string | number, level?: number): void;


  • callback: function - a function that will iterate over items of a tree collection
  • parentID: string | number - optional, the parent id. If not specified, the function will start iterating over from the root item.
  • level: number - optional, the number of levels to be iterated over. If not specified, each nested level will be visited.

Example, index, array) {
console.log("This is an item of treeCollection: ", element);
console.log("This is an index of the element: ", index);
console.log("This is an array of the elements: ", array);

The callback function takes three parameters:

element(object) the object of an item of a tree collection
index(number) the index of an item
array(array) an array with items

Change log:

added in v6.4