how to get two item from a List<> in every get request in ASP.NET Core MVC

Question

How can I get two value per get request from a List<>, For example, I have a Person List<> with six Person Ordered by ID in that List<> now in every get request using JQuery ajax() I want to get only two item from the list<>, first request will return Person with ID 1 & 2, second request will return Person with ID 3 & 4, and so forth.

I've tried

public IEnumerable<PersonViewModel> GetAllStudents()
    {
        IEnumerable<Person> dbPersons = _repo.getPersons().OrderBy(s => s.ID).Take(2);

        List<PersonViewModel> persons = new List<PersonViewModel>();
        foreach(var p in dbPersons)
        {
            persons.Add(MapDbPieToPersonViewModel(p));
        }

        return persons;
    }

But this only return first two item.

Why would it ever return anything other than first two? You always take first two. Need to pass start point and skip to that — GraemeMiller, Dec 14 '17 at 20:09
See https://stackoverflow.com/questions/2380413/paging-with-linq-for-objects — Jasen, Dec 14 '17 at 20:13
And the more mvc-specific https://stackoverflow.com/questions/446196/how-do-i-do-pagination-in-asp-net-mvc — Jasen, Dec 14 '17 at 20:16

score 0 · Accepted Answer · answered Dec 14 '17 at 20:17

0

You should use Enumerable.Skip(Int32)

public IEnumerable<PersonViewModel> GetAllStudents(int page)
{
    const int PageSize = 2;
    IEnumerable<Person> dbPersons = _repo.getPersons().OrderBy(s => s.ID).Skip(page * PageSize).Take(PageSize);

    List<PersonViewModel> persons = new List<PersonViewModel>();
    foreach(var p in dbPersons)
    {
        persons.Add(MapDbPieToPersonViewModel(p));
    }

    return persons;
}

answered Dec 14 '17 at 20:17

Albert

601
5
14

thanks, how can I pass the `page` from my ajax(), I'm new to ajax(). – Sabir Hossain Dec 14 '17 at 20:25
by adding `?page=X` to the query string – Albert Dec 14 '17 at 20:32

how to get two item from a List<> in every get request in ASP.NET Core MVC

1 Answers1