/// <summary>
/// Enables ASP.NET MVC's unobtrusive AJAX feature. An XHR request will retrieve HTML from the clicked page and replace the innerHtml of the provided element ID.
/// </summary>
/// <param name="options">The preferred Html.PagedList(...) style options.</param>
/// <param name="ajaxOptions">The ajax options that will put into the link</param>
/// <returns>The PagedListRenderOptions value passed in, with unobtrusive AJAX attributes added to the page links.</returns>
public static PagedListRenderOptions EnableUnobtrusiveAjaxReplacing(PagedListRenderOptions options, AjaxOptions ajaxOptions)
{
if (options is PagedListRenderOptions renderOptions)
{
renderOptions.FunctionToTransformEachPageLink = (liTagBuilder, aTagBuilder) =>
{
var liClass = liTagBuilder.Attributes.ContainsKey("class")
? liTagBuilder.Attributes["class"] ?? string.Empty
: string.Empty;
if (ajaxOptions != null && !liClass.Contains("disabled") && !liClass.Contains("active"))
{
foreach (var ajaxOption in ajaxOptions.ToUnobtrusiveHtmlAttributes())
{
aTagBuilder.Attributes.Add(ajaxOption.Key, ajaxOption.Value.ToString());
}
}
liTagBuilder.AppendHtml(aTagBuilder.ToString());
return(liTagBuilder);
};
}
return(options);
}
private ITagBuilder ItemSliceAndTotalText(IPagedList list, PagedListRenderOptions options)
{
var text = _tagBuilderFactory
.Create("a");
SetInnerText(text, string.Format(options.ItemSliceAndTotalFormat, list.FirstItemOnPage, list.LastItemOnPage, list.TotalItemCount));
return(WrapInListItem(text, options, "PagedList-pageCountAndLocation", "disabled"));
}
private ITagBuilder PageCountAndLocationText(IPagedList list, PagedListRenderOptions options)
{
var text = _tagBuilderFactory
.Create("a");
SetInnerText(text, string.Format(options.PageCountAndCurrentLocationFormat, list.PageNumber, list.PageCount));
return(WrapInListItem(text, options, "PagedList-pageCountAndLocation", "disabled"));
}
private ITagBuilder WrapInListItem(ITagBuilder inner, PagedListRenderOptions options, params string[] classes)
{
var li = _tagBuilderFactory
.Create("li");
foreach (var @class in classes)
{
li.AddCssClass(@class);
}
if (options != null)
{
if (options.FunctionToTransformEachPageLink != null)
{
return(options.FunctionToTransformEachPageLink(li, inner));
}
}
AppendHtml(li, TagBuilderToString(inner));
return(li);
}
private ITagBuilder Previous(IPagedList list, Func <int, string> generatePageUrl, PagedListRenderOptions options)
{
var targetPageNumber = list.PageNumber - 1;
var previous = _tagBuilderFactory
.Create("a");
AppendHtml(previous, string.Format(options.LinkToPreviousPageFormat, targetPageNumber));
previous.Attributes.Add("rel", "prev");
foreach (var c in options.PageClasses ?? Enumerable.Empty <string>())
{
previous.AddCssClass(c);
}
if (!list.HasPreviousPage)
{
return(WrapInListItem(previous, options, options.PreviousElementClass, "disabled"));
}
previous.Attributes.Add("href", generatePageUrl(targetPageNumber));
return(WrapInListItem(previous, options, options.PreviousElementClass));
}
private ITagBuilder First(IPagedList list, Func <int, string> generatePageUrl, PagedListRenderOptions options)
{
const int targetPageNumber = 1;
var first = _tagBuilderFactory
.Create("a");
AppendHtml(first, string.Format(options.LinkToFirstPageFormat, targetPageNumber));
foreach (var c in options.PageClasses ?? Enumerable.Empty <string>())
{
first.AddCssClass(c);
}
if (list.IsFirstPage)
{
return(WrapInListItem(first, options, "PagedList-skipToFirst", "disabled"));
}
first.Attributes.Add("href", generatePageUrl(targetPageNumber));
return(WrapInListItem(first, options, "PagedList-skipToFirst"));
}
public string PagedListPager(IPagedList list, Func <int, string> generatePageUrl, PagedListRenderOptions options)
{
if (options.Display == PagedListDisplayMode.Never || (options.Display == PagedListDisplayMode.IfNeeded && list.PageCount <= 1))
{
return(null);
}
var listItemLinks = new List <ITagBuilder>();
//calculate start and end of range of page numbers
var firstPageToDisplay = 1;
var lastPageToDisplay = list.PageCount;
var pageNumbersToDisplay = lastPageToDisplay;
if (options.MaximumPageNumbersToDisplay.HasValue && list.PageCount > options.MaximumPageNumbersToDisplay)
{
// cannot fit all pages into pager
var maxPageNumbersToDisplay = options.MaximumPageNumbersToDisplay.Value;
firstPageToDisplay = list.PageNumber - maxPageNumbersToDisplay / 2;
if (firstPageToDisplay < 1)
{
firstPageToDisplay = 1;
}
pageNumbersToDisplay = maxPageNumbersToDisplay;
lastPageToDisplay = firstPageToDisplay + pageNumbersToDisplay - 1;
if (lastPageToDisplay > list.PageCount)
{
firstPageToDisplay = list.PageCount - maxPageNumbersToDisplay + 1;
}
}
//first
if (options.DisplayLinkToFirstPage == PagedListDisplayMode.Always ||
(options.DisplayLinkToFirstPage == PagedListDisplayMode.IfNeeded && firstPageToDisplay > 1))
{
listItemLinks.Add(First(list, generatePageUrl, options));
}
//previous
if (options.DisplayLinkToPreviousPage == PagedListDisplayMode.Always ||
(options.DisplayLinkToPreviousPage == PagedListDisplayMode.IfNeeded && !list.IsFirstPage))
{
listItemLinks.Add(Previous(list, generatePageUrl, options));
}
//text
if (options.DisplayPageCountAndCurrentLocation)
{
listItemLinks.Add(PageCountAndLocationText(list, options));
}
//text
if (options.DisplayItemSliceAndTotal)
{
listItemLinks.Add(ItemSliceAndTotalText(list, options));
}
//page
if (options.DisplayLinkToIndividualPages)
{
//if there are previous page numbers not displayed, show an ellipsis
if (options.DisplayEllipsesWhenNotShowingAllPageNumbers && firstPageToDisplay > 1)
{
listItemLinks.Add(PreviousEllipsis(list, generatePageUrl, options, firstPageToDisplay));
}
foreach (var i in Enumerable.Range(firstPageToDisplay, pageNumbersToDisplay))
{
//show delimiter between page numbers
if (i > firstPageToDisplay && !string.IsNullOrWhiteSpace(options.DelimiterBetweenPageNumbers))
{
listItemLinks.Add(WrapInListItem(options.DelimiterBetweenPageNumbers));
}
//show page number link
listItemLinks.Add(Page(i, list, generatePageUrl, options));
}
//if there are subsequent page numbers not displayed, show an ellipsis
if (options.DisplayEllipsesWhenNotShowingAllPageNumbers &&
(firstPageToDisplay + pageNumbersToDisplay - 1) < list.PageCount)
{
listItemLinks.Add(NextEllipsis(list, generatePageUrl, options, lastPageToDisplay));
}
}
//next
if (options.DisplayLinkToNextPage == PagedListDisplayMode.Always ||
(options.DisplayLinkToNextPage == PagedListDisplayMode.IfNeeded && !list.IsLastPage))
{
listItemLinks.Add(Next(list, generatePageUrl, options));
}
//last
if (options.DisplayLinkToLastPage == PagedListDisplayMode.Always ||
(options.DisplayLinkToLastPage == PagedListDisplayMode.IfNeeded && lastPageToDisplay < list.PageCount))
{
listItemLinks.Add(Last(list, generatePageUrl, options));
}
if (listItemLinks.Any())
{
//append class to first item in list?
if (!string.IsNullOrWhiteSpace(options.ClassToApplyToFirstListItemInPager))
{
listItemLinks.First().AddCssClass(options.ClassToApplyToFirstListItemInPager);
}
//append class to last item in list?
if (!string.IsNullOrWhiteSpace(options.ClassToApplyToLastListItemInPager))
{
listItemLinks.Last().AddCssClass(options.ClassToApplyToLastListItemInPager);
}
//append classes to all list item links
foreach (var li in listItemLinks)
{
foreach (var c in options.LiElementClasses ?? Enumerable.Empty <string>())
{
li.AddCssClass(c);
}
}
}
//collapse all of the list items into one big string
var listItemLinksString = listItemLinks.Aggregate(
new StringBuilder(),
(sb, listItem) => sb.Append(TagBuilderToString(listItem)),
sb => sb.ToString());
var ul = _tagBuilderFactory
.Create("ul");
AppendHtml(ul, listItemLinksString);
foreach (var c in options.UlElementClasses ?? Enumerable.Empty <string>())
{
ul.AddCssClass(c);
}
if (options.UlElementattributes != null)
{
foreach (var c in options.UlElementattributes)
{
ul.MergeAttribute(c.Key, c.Value);
}
}
var outerDiv = _tagBuilderFactory
.Create("div");
foreach (var c in options.ContainerDivClasses ?? Enumerable.Empty <string>())
{
outerDiv.AddCssClass(c);
}
AppendHtml(outerDiv, TagBuilderToString(ul));
return(TagBuilderToString(outerDiv));
}
private ITagBuilder NextEllipsis(IPagedList list, Func <int, string> generatePageUrl, PagedListRenderOptions options, int lastPageToDisplay)
{
var next = _tagBuilderFactory
.Create("a");
AppendHtml(next, options.EllipsesFormat);
next.Attributes.Add("rel", "next");
next.AddCssClass("PagedList-skipToNext");
if (!list.HasNextPage)
{
return(WrapInListItem(next, options, options.EllipsesElementClass, "disabled"));
}
var targetPageNumber = lastPageToDisplay + 1;
next.Attributes.Add("href", generatePageUrl(targetPageNumber));
return(WrapInListItem(next, options, options.EllipsesElementClass));
}
private ITagBuilder PreviousEllipsis(IPagedList list, Func <int, string> generatePageUrl, PagedListRenderOptions options, int firstPageToDisplay)
{
var previous = _tagBuilderFactory
.Create("a");
AppendHtml(previous, options.EllipsesFormat);
previous.Attributes.Add("rel", "prev");
previous.AddCssClass("PagedList-skipToPrevious");
if (!list.HasPreviousPage)
{
return(WrapInListItem(previous, options, options.EllipsesElementClass, "disabled"));
}
var targetPageNumber = firstPageToDisplay - 1;
previous.Attributes.Add("href", generatePageUrl(targetPageNumber));
return(WrapInListItem(previous, options, options.EllipsesElementClass));
}
private ITagBuilder Next(IPagedList list, Func <int, string> generatePageUrl, PagedListRenderOptions options)
{
var targetPageNumber = list.PageNumber + 1;
var next = _tagBuilderFactory
.Create("a");
AppendHtml(next, string.Format(options.LinkToNextPageFormat, targetPageNumber));
next.Attributes.Add("rel", "next");
foreach (var c in options.PageClasses ?? Enumerable.Empty <string>())
{
next.AddCssClass(c);
}
if (!list.HasNextPage)
{
return(WrapInListItem(next, options, options.NextElementClass, "disabled"));
}
next.Attributes.Add("href", generatePageUrl(targetPageNumber));
return(WrapInListItem(next, options, options.NextElementClass));
}
private ITagBuilder Page(int i, IPagedList list, Func <int, string> generatePageUrl, PagedListRenderOptions options)
{
var format = options.FunctionToDisplayEachPageNumber
?? (pageNumber => string.Format(options.LinkToIndividualPageFormat, pageNumber));
var targetPageNumber = i;
var page = i == list.PageNumber
? _tagBuilderFactory
.Create("span")
: _tagBuilderFactory
.Create("a");
SetInnerText(page, format(targetPageNumber));
foreach (var c in options.PageClasses ?? Enumerable.Empty <string>())
{
page.AddCssClass(c);
}
if (i == list.PageNumber)
{
return(WrapInListItem(page, options, options.ActiveLiElementClass));
}
page.Attributes.Add("href", generatePageUrl(targetPageNumber));
return(WrapInListItem(page, options));
}
