RU EN
May 16, 2024

You have been doing pagination wrong in .NET 6

Author:
Source:
Views:
4546
You have been doing pagination wrong in .NET 6 favorites 0

Pagination is in front of us everyday yet we take it for granted kind of like we do with most things. It’s what chunks huge lists of data (blog posts, articles, products) into pages so we can navigate through data.

This is how you did pagination until this point.

Pagination

using System;

public class Article
{
    public int Id;
    public string Title;
    public string Content;
    public int AuthorId;
    
    public List<Article> GetArticles()
    {
        return new List<Article> {
            new Article {Id = 1, Title = "Best title one", Content = "Amazing content", AuthorId = 1},
            new Article {Id = 2, Title = "Another title", Content = "More amazing content", AuthorId = 1},
            new Article {Id = 3, Title = "Unicorns", Content = "Even more amazing content", AuthorId = 1},
            new Article {Id = 4, Title = "Best title one", Content = "Amazing content", AuthorId = 1},
            new Article {Id = 5, Title = "Another title", Content = "More amazing content", AuthorId = 1},
            new Article {Id = 6, Title = "Unicorns", Content = "Even more amazing content", AuthorId = 1},
            new Article {Id = 7, Title = "Best title one", Content = "Amazing content", AuthorId = 1},
            new Article {Id = 8, Title = "Another title", Content = "More amazing content", AuthorId = 1},
            new Article {Id = 9, Title = "Unicorns", Content = "Even more amazing content", AuthorId = 1},
            new Article {Id = 10, Title = "Best title one", Content = "Amazing content", AuthorId = 1},
            new Article {Id = 11, Title = "Another title", Content = "More amazing content", AuthorId = 1},
            new Article {Id = 12, Title = "Unicorns", Content = "Even more amazing content", AuthorId = 1},
        };
    }
}

public class Program
{
    public static void Main()
    {
        List<Article> articles = new Article().GetArticles();
        int pageNumber = 1;
        int itemsPerPage = 5;

        IEnumerable<Article> page = articles.Skip((pageNumber - 1) * itemsPerPage).Take(itemsPerPage);

        Console.WriteLine($"Page: {pageNumber}");
        foreach(Article article in page)
        {
            Console.WriteLine($"    Id: {article.Id}, Title:{article.Title}, Content:{article.Content}, AuthorId:{article.AuthorId}");
        }
    }
}

And now this is how you can achieve the same result but in a more readable way using the Chunk method.

Chunk

using System;

public class Article
{
    public int Id;
    public string Title;
    public string Content;
    public int AuthorId;
    
    public List<Article> GetArticles()
    {
        return new List<Article> {
            new Article {Id = 1, Title = "Best title one", Content = "Amazing content", AuthorId = 1},
            new Article {Id = 2, Title = "Another title", Content = "More amazing content", AuthorId = 1},
            new Article {Id = 3, Title = "Unicorns", Content = "Even more amazing content", AuthorId = 1},
            new Article {Id = 4, Title = "Best title one", Content = "Amazing content", AuthorId = 1},
            new Article {Id = 5, Title = "Another title", Content = "More amazing content", AuthorId = 1},
            new Article {Id = 6, Title = "Unicorns", Content = "Even more amazing content", AuthorId = 1},
            new Article {Id = 7, Title = "Best title one", Content = "Amazing content", AuthorId = 1},
            new Article {Id = 8, Title = "Another title", Content = "More amazing content", AuthorId = 1},
            new Article {Id = 9, Title = "Unicorns", Content = "Even more amazing content", AuthorId = 1},
            new Article {Id = 10, Title = "Best title one", Content = "Amazing content", AuthorId = 1},
            new Article {Id = 11, Title = "Another title", Content = "More amazing content", AuthorId = 1},
            new Article {Id = 12, Title = "Unicorns", Content = "Even more amazing content", AuthorId = 1},
        };
    }
}

public class Program
{
    public static void Main()
    {
        List<Article> articles = new Article().GetArticles();
        int pageNumber = 1;
        int itemsPerPage = 5;

        IEnumerable<Article[]> allPages = articles.Chunk(itemsPerPage);

        Console.WriteLine($"Page: {pageNumber}");
       
        foreach(Article article in allPages.ElementAt(pageNumber - 1))
        {
            Console.WriteLine($"    Id: {article.Id}, Title:{article.Title}, Content:{article.Content}, AuthorId:{article.AuthorId}");
        }
    }
}

There’s nothing wrong with using the first method to do pagination. The Chunk method is a new way of doing achieving the same result but with a cleared code. It takes only one parameter, the maximum size of each chunk (largest numbers of items per page). Is important to note that the Chunk method is only available in .NET 6.

Conclusion

This is another way to do things, another tool in your arsenal so you can use both. 

Похожее
May 16, 2022
Author: Hussein NM
In this article, I will show the most performant way to write queries for a collection of objects in .Net Core. The article discusses the common methods of LINQ and their comparison. After reading this article, you may have to...
Nov 12, 2020
Author: Joydip Kanjilal
Lazy initialization is a technique that defers the creation of an object until the first time it is needed. In other words, initialization of the object happens only on demand. Note that the terms lazy initialization and lazy instantiation mean...
Nov 30, 2023
Author: Dev·edium
QUIC (Quick UDP Internet Connections) is a new transport protocol for the Internet that runs on top of User Datagram Protocol (UDP) QUIC (Quick UDP Internet Connections) is a new transport protocol for the Internet that runs on top of...
Jan 10, 2024
Author: MESCIUS inc.
In today’s connected world, data is piling up very fast. We are generating more data than ever in human history, and a lot of this data is getting stored in non-relational formats like JSON documents. JSON has become a ubiquitous...
Написать сообщение
Тип
Почта
Имя
*Сообщение