PagedList

What is this?

PagedList is a library that enables you to easily take an IEnumerable/IQueryable, chop it up into "pages", and grab a specific "page" by an index. PagedList.Mvc allows you to take that "page" and display a pager control that has links like "Previous", "Next", etc.

How do I use it?

1. Install "PagedList.Mvc" via NuGet - that will automatically install "PagedList" as well.
2. In your controller code, call ToPagedList off of your IEnumerable/IQueryable passing in the page size and which page you want to view.
3. Pass the result of ToPagedList to your view where you can enumerate over it - its still an IEnumerable, but only contains a subset of the original data.
4. Call Html.PagedListPager, passing in the instance of the PagedList and a function that will generate URLs for each page to see a paging control.

---

Example

/Controllers/ProductController.cs

public class ProductController : Controller
{
	public object Index(int? page)
	{
		var products = MyProductDataSource.FindAllProducts(); //returns IQueryable<Product> representing an unknown number of products. a thousand maybe?

		var pageNumber = page ?? 1; // if no page was specified in the querystring, default to the first page (1)
		var onePageOfProducts = products.ToPagedList(pageNumber, 25); // will only contain 25 products max because of the pageSize
		
		ViewBag.OnePageOfProducts = onePageOfProducts;
		return View();
	}
}

/Views/Products/Index.cshtml

@{
	ViewBag.Title = "Product Listing"
}
@using PagedList.Mvc; //import this so we get our HTML Helper
@using PagedList; //import this so we can cast our list to IPagedList (only necessary because ViewBag is dynamic)

<!-- import the included stylesheet for some (very basic) default styling -->
<link href="/Content/PagedList.css" rel="stylesheet" type="text/css" />

<!-- loop through each of your products and display it however you want. we're just printing the name here -->
<h2>List of Products</h2>
<ul>
	@foreach(var product in ViewBag.OnePageOfProducts){
		<li>@product.Name</li>
	}
</ul>

<!-- output a paging control that lets the user navigation to the previous page, next page, etc -->
@Html.PagedListPager( (IPagedList)ViewBag.OnePageOfProducts, page => Url.Action("Index", new { page }) )

Example 2: Manual Paging

/Controllers/ProductController.cs

In some cases you do not have access something capable of creating an IQueryable, such as when using .Net's built-in MembershipProvider's GetAllUsers method. This method offers paging, but not via IQueryable. Luckily PagedList still has your back (note the use of StaticPagedList):

public class UserController : Controller
{
	public object Index(int? page)
	{
		var pageIndex = (page ?? 1) - 1; //MembershipProvider expects a 0 for the first page
		var pageSize = 10;
		int totalUserCount; // will be set by call to GetAllUsers due to _out_ paramter :-|

		var users = Membership.GetAllUsers(pageIndex, pageSize, out totalUserCount);
		var usersAsIPagedList = new StaticPagedList<MembershipUser>(users, pageIndex + 1, pageSize, totalUserCount);

		ViewBag.OnePageOfUsers = usersAsIPagedList;
		return View();
	}
}

---

Split and Partition Extension Methods

You can split an enumerable up into n equal-sized objects using the .Split extension method:

var deckOfCards = new DeckOfCards(); //there are 52 cards in the deck
var splitDeck = deckOfCards.Split(2).ToArray();

Assert.Equal(26, splitDeck[0].Count());
Assert.Equal(26, splitDeck[1].Count());

You can split an enumerable up into n pages, each with a maximum of m items using the .Partition extension method:

var deckOfCards = new DeckOfCards(); //52 cards
var hands = deckOfCards.Partition(5).ToArray();

Assert.Equal(11, hands.Count());
Assert.Equal(5, hands.First().Count());
Assert.Equal(2, hands.Last().Count()); //10 hands have 5 cards, last hand only has 2 cards

---

Pager Configurations

Styling the Pager Yourself

The HTML output by Html.PagedListPager is configured to be styled automatically by the Twitter Bootstrap stylesheet, if present. Here is what it looks like without using Twitter Bootstrap:

Out-of-the-box Pager Configurations

<h3>Default Paging Control</h3>
@Html.PagedListPager((IPagedList)ViewBag.OnePageOfProducts, page => Url.Action("Index", new { page = page }))

<h3>Minimal Paging Control</h3>
@Html.PagedListPager((IPagedList)ViewBag.OnePageOfProducts, page => Url.Action("Index", new { page = page }), PagedListRenderOptions.Minimal)

<h3>Minimal Paging Control w/ Page Count Text</h3>
@Html.PagedListPager((IPagedList)ViewBag.OnePageOfProducts, page => Url.Action("Index", new { page = page }), PagedListRenderOptions.MinimalWithPageCountText)

<h3>Minimal Paging Control w/ Item Count Text</h3>
@Html.PagedListPager((IPagedList)ViewBag.OnePageOfProducts, page => Url.Action("Index", new { page = page }), PagedListRenderOptions.MinimalWithItemCountText)

<h3>Page Numbers Only</h3>
@Html.PagedListPager((IPagedList)ViewBag.OnePageOfProducts, page => Url.Action("Index", new { page = page }), PagedListRenderOptions.PageNumbersOnly)

<h3>Only Show Five Pages At A Time</h3>
@Html.PagedListPager((IPagedList)ViewBag.OnePageOfProducts, page => Url.Action("Index", new { page = page }), PagedListRenderOptions.OnlyShowFivePagesAtATime)

Custom Pager Configurations

You can instantiate PagedListRenderOptions yourself to create custom configurations. All elements/links have discrete CSS classes applied to make styling easier as well.

<h3>Custom Wording (<em>Spanish Translation Example</em>)</h3>
@Html.PagedListPager((IPagedList)ViewBag.OnePageOfProducts, page => Url.Action("Index", new { page = page }), new PagedListRenderOptions { LinkToFirstPageFormat = "<< Primera", LinkToPreviousPageFormat = "< Anterior", LinkToNextPageFormat = "Siguiente >", LinkToLastPageFormat = "&Uacute;ltima >>" })

<h3>Show Range of Items For Each Page</h3>
@Html.PagedListPager((IPagedList)ViewBag.OnePageOfProducts, page => Url.Action("Index", new { page = page }), new PagedListRenderOptions { FunctionToDisplayEachPageNumber = page => ((page - 1) * ViewBag.Names.PageSize + 1).ToString() + "-" + (((page - 1) * ViewBag.Names.PageSize) + ViewBag.Names.PageSize).ToString(), MaximumPageNumbersToDisplay = 5 })

<h3>With Delimiter</h3>
@Html.PagedListPager((IPagedList)ViewBag.OnePageOfProducts, page => Url.Action("Index", new { page = page }), new PagedListRenderOptions { DelimiterBetweenPageNumbers = "|" })

---

License

Licensed under the MIT License.