ReApptor TypeScript PagedList

It is a complete, fully tested pagination library for splitting the array into pages and selecting a specific page by an index. It includes an IPagedList interface, a PagedList container, and an array toPagedList extension written in TypeScript.

Installation

Install from the command line:

npm install @reapptor/ts-paged-list

Install via package.json:

"@reapptor/ts-paged-list": "^1.*"

Usage

Add import "@reapptor/ts-paged-list"; into the main project file (i.e. index.ts) to register extensions.

Use array extension toPagedList to select the page a specific page by page index and size, for example: [1,2,3,4,5].toPagedList(1, 2).

See more:

IPagedList interface description.
ToPagedList extension description.
Some examples

License

The ReApptor TypeScript PagedList package is licensed under the terms of the MIT license and is available for free.

Testing

The code is 100% covered by the JEST tests.
The generated coverage result is here:
Coverage Summary

Other projects

ReApptor.TypeScript.Linq @reapptor/ts-linq
It is a complete, fully tested analog of C# Language-Integrated Query (LINQ) written in TypeScript.

IPagedList

Represents a subset of input items that can be individually accessed by index and
contains metadata about the superset collection of objects this subset was created from.

export default interface IPagedList<out T = {}> {

    /**
     * The page items.
     */
    readonly items: readonly T[];

    /**
     * The one-based page index is in the superset.
     */
    readonly pageNumber: number;

    /**
     * The maximum size of any page.
     */
    readonly pageSize: number;

    /**
     * The total number of pages within the superset
     */
    readonly pageCount: number;

    /**
     * The total number of elements contained within the superset.
     */
    readonly totalItemCount: number;

    /**
     * Returns true if the page number is higher than 1, showing that the subset is not the first within the superset.
     */
    readonly hasPreviousPage: boolean;

    /**
     * Returns true if the page number is less than the page count, showing that the subset is not the latest within the superset.
     */
    readonly hasNextPage: boolean;

    /**
     * Returns true if the page number is 1, showing that the subset is the first within the superset.
     */
    readonly isFirstPage: boolean;

    /**
     * Returns true if the page number equals the page count, showing that the subset is the last within the superset.
     */
    readonly isLastPage: boolean;

    /**
     * The zero-based index of the first item in the paged subset within the superset.
     */
    readonly firstItemIndex: number;

    /**
     * The zero-based index of the last item in the paged subset within the superset.
     */
    readonly lastItemIndex: number;
}

Array extension functions

ToPagedList

Splits the input superset collection into pages (subsets) and returns the specific page (subset) by an index.

/**
 * Splits the input superset collection into pages (subsets) and returns the specific page (subset) by an index.
 * @param pageNumber - The page index is in the superset starting from 1.
 * @param pageSize - The maximum size of any page.
 * @returns IPagedList<T> - An IPagedList<T> object object that contains the specified subset and metadata about the input superset collection of objects this subset was created from.
 */
toPagedList(pageNumber: number, pageSize: number): IPagedList<T>;

Examples

Example #1

Selecting the second page from an array of numbers with page size 2.

const input: number[] = [1, 2, 3, 4, 5];

const page: IPagedList<number> = input.toPagedList(2, 2);

console.log(`page #${page.pageNumber} from ${page.pageCount}`);
console.log(`page items [${page.items}] from [${input}]`);
console.log("");
console.log("pageSize = ", page.pageSize);
console.log("totalItemCount = ", page.totalItemCount);
console.log("hasPreviousPage = ", page.hasPreviousPage);
console.log("hasNextPage = ", page.hasNextPage);
console.log("isFirstPage = ", page.isFirstPage);
console.log("isLastPage = ", page.isLastPage);
console.log("firstItemIndex = ", page.firstItemIndex);
console.log("lastItemIndex = ", page.lastItemIndex);

Code produces the following output:

 page 2/3
 page items = [ 3, 4 ] from [ 1, 2, 3, 4, 5 ]
 
 pageSize = 2
 totalItemCount = 5
 hasPreviousPage = true
 hasNextPage = true
 isFirstPage = false
 isLastPage = false
 firstItemIndex = 2
 lastItemIndex = 3

Example #2

The initializing of the empty page.

const page: IPagedList = [].toPagedList(1, 100);

console.log(`page #${page.pageNumber} from ${page.pageCount}`);
console.log(`page items [${page.items}] from []`);
console.log("");
console.log("pageSize = ", page.pageSize);
console.log("totalItemCount = ", page.totalItemCount);
console.log("hasPreviousPage = ", page.hasPreviousPage);
console.log("hasNextPage = ", page.hasNextPage);
console.log("isFirstPage = ", page.isFirstPage);
console.log("isLastPage = ", page.isLastPage);
console.log("firstItemIndex = ", page.firstItemIndex);
console.log("lastItemIndex = ", page.lastItemIndex);

Code produces the following output:

 page 1/1
 page items = [] from []
 
 pageSize = 100
 totalItemCount = 0
 hasPreviousPage = false
 hasNextPage = false
 isFirstPage = true
 isLastPage = true
 firstItemIndex = 0
 lastItemIndex = 0

Hashtags

#pagedlist #paged-list #ts-paged-list #pagination #ts #typescript #npm #github

reapptor / reapptor.typescript.pagedlist Goto Github PK