public override void Process(TagHelperContext context, TagHelperOutput output)
{
if (PagingModel == null)
{
// allow for passing in the settings separately
PagingModel = new PaginationSettings();
PagingModel.CurrentPage = PageNumber;
PagingModel.ItemsPerPage = PageSize;
PagingModel.TotalItems = TotalItems;
PagingModel.MaxPagerItems = MaxPagerItems;
PagingModel.SuppressEmptyNextPrev = SuppressEmptyNextPrev;
PagingModel.SuppressInActiveFirstLast = SuppressInActiveFirstLast;
}
if (ShowFirstLast)
{
PagingModel.ShowFirstLast = true;
}
if (!ShowNumbered)
{
PagingModel.ShowNumbered = false;
}
if (UseReverseIncrement)
{
PagingModel.UseReverseIncrement = true;
if (SuppressEmptyNextPrev)
{
PagingModel.SuppressEmptyNextPrev = true;
}
}
int totalPages = (int)Math.Ceiling(PagingModel.TotalItems / (double)PagingModel.ItemsPerPage);
// don't render if only 1 page
if (totalPages <= 1)
{
output.SuppressOutput();
return;
}
//change the cs-pager element into a ul
output.TagName = "ul";
string querySeparator;
//prepare things needed by generatpageeurl function
TagBuilder linkTemplate = GenerateLinkTemplate();
baseHref = linkTemplate.Attributes["href"] ?? string.Empty;
querySeparator = baseHref.Contains("?") ? "&" : "?";
baseHref = baseHref + querySeparator + PageNumberParam + "=";
List <PaginationLink> links = linkBuilder.BuildPaginationLinks(
PagingModel,
GeneratePageUrl,
FirstPageText,
FirstPageTitle,
PreviousPageText,
PreviousPageTitle,
NextPageText,
NextPageTitle,
LastPageText,
LastPageTitle,
"...");
foreach (PaginationLink link in links)
{
var li = new TagBuilder("li");
if (link.IsCurrent)
{
li.AddCssClass(LiCurrentCssClass);
}
if (!link.Active)
{
li.AddCssClass(LiNonActiveCssClass);
}
var a = new TagBuilder("a");
if (link.Active && (link.Url.Length > 0))
{
a.MergeAttribute("href", link.Url);
}
else
{
a.MergeAttribute("href", "#");
}
if (link.Text == "«")
{
//a.InnerHtml = "«";
a.InnerHtml.AppendHtml("«");
}
else if (link.Text == "»")
{
//a.InnerHtml = "»";
a.InnerHtml.AppendHtml("»");
}
else
{
a.InnerHtml.Append(link.Text);
}
if (link.Title.Length > 0)
{
a.MergeAttribute("title", link.Title);
}
if (AjaxTarget.Length > 0)
{
a.MergeAttribute("data-ajax", "true");
a.MergeAttribute("data-ajax-mode", AjaxMode);
a.MergeAttribute("data-ajax-update", AjaxTarget);
}
li.InnerHtml.Append(a);
output.Content.Append(li);
}
output.Attributes.Clear();
output.Attributes.Add("class", UlCssClass);
}
/// <summary>
/// the problem with paging is when you have too many pages
/// to fit in the pager based on PaginationSettings.MaxPagerItems
/// you need a strategy to leave out links for some pages
/// while still being possible to navigate to any page
/// this class implements one such strategy (implemented by Martijn Boland)
/// if you want to implement a different strategy you can plugin your own
/// IBuildPaginationLinks implementation
/// </summary>
/// <param name="paginationSettings"></param>
/// <param name="generateUrl"></param>
/// <param name="firstPageText"></param>
/// <param name="firstPageTitle"></param>
/// <param name="previousPageText"></param>
/// <param name="previousPageTitle"></param>
/// <param name="nextPageText"></param>
/// <param name="nextPageTitle"></param>
/// <param name="lastPageText"></param>
/// <param name="lastPageTitle"></param>
/// <param name="spacerText"></param>
/// <returns></returns>
public List <PaginationLink> BuildPaginationLinks(
PaginationSettings paginationSettings,
Func <long, string> generateUrl,
string firstPageText,
string firstPageTitle,
string previousPageText,
string previousPageTitle,
string nextPageText,
string nextPageTitle,
string lastPageText,
string lastPageTitle,
string spacerText = "...")
{
List <PaginationLink> paginationLinks = new List <PaginationLink>();
long totalPages = (long)Math.Ceiling(paginationSettings.TotalItems / (double)paginationSettings.ItemsPerPage);
// First page
if (paginationSettings.ShowFirstLast)
{
var isActive = paginationSettings.CurrentPage > 1;
if (isActive || !paginationSettings.SuppressInActiveFirstLast)
{
paginationLinks.Add(
new PaginationLink
{
Active = isActive,
Text = firstPageText,
Title = firstPageTitle,
PageNumber = 1,
Url = generateUrl(1)
});
}
}
// Previous page
if (paginationSettings.UseReverseIncrement)
{
var isActive = paginationSettings.CurrentPage < totalPages;
//SuppressEmptyNextPrev
if (isActive)
{
paginationLinks.Add(
new PaginationLink
{
Active = true,
PageNumber = paginationSettings.CurrentPage + 1,
Text = previousPageText,
Title = previousPageTitle,
Url = generateUrl(paginationSettings.CurrentPage + 1)
});
}
else
{
if (!paginationSettings.SuppressEmptyNextPrev)
{
paginationLinks.Add(
new PaginationLink
{
Active = false,
Text = previousPageText,
PageNumber = totalPages
});
}
}
}
else
{
var isActive = paginationSettings.CurrentPage > 1;
if (isActive)
{
paginationLinks.Add(new PaginationLink
{
Active = true,
Text = previousPageText,
Title = previousPageTitle,
PageNumber = paginationSettings.CurrentPage - 1,
Url = generateUrl(paginationSettings.CurrentPage - 1)
});
}
else
{
if (!paginationSettings.SuppressEmptyNextPrev)
{
paginationLinks.Add(new PaginationLink
{
Active = false,
Text = previousPageText,
PageNumber = 1,
Url = generateUrl(1)
});
}
}
}
if (paginationSettings.ShowNumbered)
{
var start = 1L;
var end = totalPages;
var nrOfPagesToDisplay = paginationSettings.MaxPagerItems;
if (totalPages > nrOfPagesToDisplay)
{
var middle = (long)Math.Ceiling(nrOfPagesToDisplay / 2d) - 1;
var below = (paginationSettings.CurrentPage - middle);
var above = (paginationSettings.CurrentPage + middle);
if (below < 2)
{
above = nrOfPagesToDisplay;
below = 1;
}
else if (above > (totalPages - 2))
{
above = totalPages;
below = (totalPages - nrOfPagesToDisplay + 1);
}
start = below;
end = above;
}
if (start > 1)
{
paginationLinks.Add(new PaginationLink
{
Active = true,
PageNumber = 1,
IsCurrent = (paginationSettings.CurrentPage == 1 ? true : false),
Text = "1",
Url = generateUrl(1)
});
if (start > 3)
{
paginationLinks.Add(new PaginationLink
{
Active = true,
PageNumber = 2,
IsCurrent = (paginationSettings.CurrentPage == 2 ? true : false),
Text = "2",
Url = generateUrl(2)
});
}
if (start > 2)
{
paginationLinks.Add(new PaginationLink
{
Active = false,
Text = spacerText,
IsSpacer = true
});
}
}
for (var i = start; i <= end; i++)
{
if (i == paginationSettings.CurrentPage || (paginationSettings.CurrentPage <= 0 && i == 1))
{
paginationLinks.Add(new PaginationLink
{
Active = true,
PageNumber = i,
IsCurrent = (paginationSettings.CurrentPage == i ? true : false),
Text = i.ToString(),
Url = generateUrl(i)
});
}
else
{
paginationLinks.Add(new PaginationLink
{
Active = true,
PageNumber = i,
Text = i.ToString(),
IsCurrent = (paginationSettings.CurrentPage == i ? true : false),
Url = generateUrl(i)
});
}
}
if (end < totalPages)
{
if (end < totalPages - 1)
{
paginationLinks.Add(new PaginationLink
{
Active = false,
Text = spacerText,
IsSpacer = true
});
}
if (totalPages - 2 > end)
{
paginationLinks.Add(new PaginationLink
{
Active = true,
PageNumber = totalPages - 1,
Text = (totalPages - 1).ToString(),
IsCurrent = (paginationSettings.CurrentPage == (totalPages - 1) ? true : false),
Url = generateUrl(totalPages - 1)
});
}
paginationLinks.Add(new PaginationLink
{
Active = true,
PageNumber = totalPages,
Text = totalPages.ToString(),
IsCurrent = (paginationSettings.CurrentPage == totalPages ? true : false),
Url = generateUrl(totalPages)
});
}
}
// Next page
if (paginationSettings.UseReverseIncrement)
{
//SuppressEmptyNextPrev
var isActive = paginationSettings.CurrentPage > 1;
if (isActive)
{
paginationLinks.Add(
new PaginationLink
{
Active = true,
Text = nextPageText,
Title = nextPageTitle,
PageNumber = paginationSettings.CurrentPage - 1,
Url = generateUrl(paginationSettings.CurrentPage - 1)
});
}
else
{
if (!paginationSettings.SuppressEmptyNextPrev)
{
paginationLinks.Add(
new PaginationLink
{
Active = false,
Text = nextPageText,
PageNumber = 1,
Url = generateUrl(1)
});
}
}
//paginationLinks.Add(
// paginationSettings.CurrentPage > 1 ? new PaginationLink
// {
// Active = true,
// Text = nextPageText,
// Title = nextPageTitle,
// PageNumber = paginationSettings.CurrentPage + 1,
// Url = generateUrl(paginationSettings.CurrentPage + 1)
// } : new PaginationLink
// {
// Active = false,
// Text = nextPageText,
// PageNumber = 1,
// Url = generateUrl(1)
// });
}
else
{
var isActive = paginationSettings.CurrentPage < totalPages;
if (isActive)
{
paginationLinks.Add(new PaginationLink
{
Active = true,
PageNumber = paginationSettings.CurrentPage + 1,
Text = nextPageText,
Title = nextPageTitle,
Url = generateUrl(paginationSettings.CurrentPage + 1)
});
}
else
{
if (!paginationSettings.SuppressEmptyNextPrev)
{
paginationLinks.Add(new PaginationLink
{
Active = false,
Text = nextPageText,
PageNumber = totalPages
});
}
}
}
// Last page
if (paginationSettings.ShowFirstLast)
{
var isActive = paginationSettings.CurrentPage < totalPages;
if (isActive || !paginationSettings.SuppressInActiveFirstLast)
{
paginationLinks.Add(new PaginationLink
{
Active = isActive,
Text = lastPageText,
Title = lastPageTitle,
PageNumber = totalPages,
Url = generateUrl(totalPages)
});
}
}
return(paginationLinks);
}