Поиск  
Always will be ready notify the world about expectations as easy as possible: job change page
May 16

You have been doing pagination wrong in .NET 6

Author:
Source:
Views:
3224

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
Nov 19, 2020
We will demonstrate how to setup Elasticsearch and learn how to write basics statements. You will learn about the structure, commands, tools in Elasticsearch API and get it up and running using standard settings. Introduction We will be talking about...
Jun 5, 2023
Author: Juan Alberto España Garcia
In this section, we’ll explore the world of unit testing in C# and .NET, learn what unit testing is, why it’s important, and the landscape of testing frameworks and tools available to developers. What is Unit Testing? Unit testing is...
Aug 18, 2023
Author: Alex Maher
C# Data Structures Handbook! Every decision in programming is a silent influencer of performance and clarity. In C#, one such vital choice is selecting the right data structure. Data structures are foundational pillars. These structures are where data lives, breathes,...
Apr 4
Author: João Simões
Performance comparison between ToList and ToArray Ever since Microsoft introduced Language Integrated Query to the .NET framework (also known as LINQ) developers have been using it extensively to work with collections. From a simple filter, to an aggregation, to a...
Написать сообщение
Тип
Почта
Имя
*Сообщение