Part 63 - Implement paging in asp.net mvc

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In this video we will discuss, implementing pagination in an asp.net mvc application. Please watch Part 62, before proceeding.



By the end of this video, the index page should support both search functionality and pagination as shown below.




Step 1: Install PagedList.Mvc using NuGet package manager. PagedList.Mvc is dependent on PagedList. Installing PagedList.Mvc will automatically install PagedList package as well.


Step 2: Include the following using statements in HomeController.cs file
using PagedList.Mvc;
using PagedList;

Modify the Index() action method as shown below. Notice that we are passing page parameter to this function. This parameter is used for specifying the page number. This parameter can be null, and that's the reason we have chosen a nullable integer. We convert the list, to a paged list, using ToPagedList(). Also, notice that, we are using null-coalescing operator. If  the "page" parameter is null, then 1 is passed as the page number, else, the value contained in the "page" parameter is used as the page number.
public ActionResult Index(string searchBy, string search, int? page)
{
    if (searchBy == "Gender")
    {
        return View(db.Employees.Where(x => x.Gender == search || search == null).ToList().ToPagedList(page ?? 1, 3));
    }
    else
    {
        return View(db.Employees.Where(x => x.Name.StartsWith(search) || search == null).ToList().ToPagedList(page ?? 1, 3));
    }
}

Step 3: Make the following modifications to Index.cshtml view
a) Include the following 2 using statements on the view.
@using PagedList.Mvc;
@using PagedList;

b) The model for the view should be IPagedList<Employee>.
@model IPagedList<MVCDemo.Models.Employee>

c) Since, we have changed the model of the view, from IEnumerable<MVCDemo.Models.Employee> to IPagedList<MVCDemo.Models.Employee>, change the section that displays table headings as shown below.
<tr>
    <th>
        @Html.DisplayNameFor(model => model.First().Name)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.First().Gender)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.First().Email)
    </th>
    <th>Action</th>
</tr>

d) Finally to display page numbers for paging
@Html.PagedListPager(Model, page => Url.Action("Index", new { page, searchBy = Request.QueryString["searchBy"], search = Request.QueryString["search"] }))

e) If you want to display the pager, only if there are more than 1 page
@Html.PagedListPager(Model, page => Url.Action("Index", new { page, searchBy = Request.QueryString["searchBy"], search = Request.QueryString["search"] }), new PagedListRenderOptions() { Display = PagedListDisplayMode.IfNeeded })

f) If you want to display, the current active page and the total number of pages
@Html.PagedListPager(Model, page => Url.Action("Index", new { page, searchBy = Request.QueryString["searchBy"], search = Request.QueryString["search"] }), new PagedListRenderOptions() { Display = PagedListDisplayMode.IfNeeded, DisplayPageCountAndCurrentLocation = true })

g) If you want to display the number of rows displayed, of the total number of rows available.
@Html.PagedListPager(Model, page => Url.Action("Index", new { page, searchBy = Request.QueryString["searchBy"], search = Request.QueryString["search"] }), new PagedListRenderOptions() { Display = PagedListDisplayMode.IfNeeded, DisplayItemSliceAndTotal = true })