js-helper-functions

Javascript Utility Functions

TypeScript utility functions.

countItemsInMultidimensionalObject

A function that recursively counts the number of selected items in a nested data structure. This function is particularly useful when dealing with hierarchical selection states such as those found in tree views, nested checklists, or multi-level category pickers.

✨ Features

• Handles both arrays and deeply nested objects.
• Returns a detailed breakdown of item counts per level.
• Provides a total count of all selected items.

Data Type

type NestedObject = {
  [key: string]: Node | string[];
};

Parameeter

Name	Type	Description
data	NestedObject Or string[]	A nested object or array representing selected items.

📤 Returns

• If the input is a flat array, it returns a number representing the count of items.
• If the input is a nested object, it returns an object of type SelectionCountsResult:

{
  total: number;     // Total count of items in the entire structure
  result: {
    [key: string]: number | { ...nested_object }
  }
}

Example

const selection = {
  fruits: ["apple", "banana"],
  vegetables: {
    root: ["carrot", "beet"],
    leafy: ["spinach"],
  },
  grains: {
    rice: ["basmati"],
    wheat: [],
  },
};

const result = countItemsInMultidimensionalObject(selection);
console.log(result);

result:

{
  total: 6,
  result: {
    fruits: 2,
    vegetables: {
      root: 2,
      leafy: 1
    },
    grains: {
      rice: 1,
      wheat: 0
    }
  }
}