private static int GetStartingPage(PagerData pagerData, PagerSettings settings)
{
// Total pages = 5 = number of pages to display.. so starting page is 1;
if (pagerData.CurrentPage <= settings.NumberPagesToDisplay)
{
return(1);
}
int range = GetRange(pagerData.CurrentPage, settings.NumberPagesToDisplay);
int totalRanges = GetTotalRanges(pagerData.TotalPages, settings.NumberPagesToDisplay);
// Current page = 17
// Total pages = 18
// Pages to show = 5
// Range = 4
// Starting page = 14, 15, 16, 17, 18
if (range == totalRanges)
{
return((pagerData.TotalPages - settings.NumberPagesToDisplay) + 1);
}
// current page = 7
// Total pages = 18
// Pages to show = 5
// Range = 2
// starting page = 6
range--;
return((range * settings.NumberPagesToDisplay) + 1);
}
/// <summary>
/// Build page numbers list.
/// </summary>
/// <param name="ctx">Pager action context</param>
/// <param name="pagerSettings"></param>
public static void BuildPageNumbersList(IList <PageNumber> pageNumbersList, PagerData pagerData, PagerSettings pagerSettings)
{
// Clear existing to build them.
pageNumbersList.Clear();
// Build each page number.
for (int ndx = pagerData.StartingPage; ndx <= pagerData.EndingPage; ndx++)
{
string cssClass = (ndx == pagerData.CurrentPage) ? pagerSettings.CssCurrentPage : string.Empty;
pageNumbersList.Add(new PageNumber(ndx, cssClass));
}
}
private static int GetEndingPage(PagerData pagerData, PagerSettings settings)
{
// Total pages = 5 = Number to display 1 - 5
if (pagerData.TotalPages <= settings.NumberPagesToDisplay)
{
return(pagerData.TotalPages);
}
int range = GetRange(pagerData.CurrentPage, settings.NumberPagesToDisplay);
int totalRanges = GetTotalRanges(pagerData.TotalPages, settings.NumberPagesToDisplay);
if (range == totalRanges)
{
return(pagerData.TotalPages);
}
// if page = 8, ending page is 10.
return(range * settings.NumberPagesToDisplay);
}
public void Calculate(PagerData pagerData, PagerSettings pagerSettings)
{
// Check bounds.
if (pagerData.CurrentPage < 0)
{
pagerData.CurrentPage = 1;
}
if (pagerData.CurrentPage > pagerData.TotalPages)
{
pagerData.CurrentPage = 1;
}
int currentPage = pagerData.CurrentPage;
// Calculate the starting and ending page.
pagerData.StartingPage = GetStartingPage(pagerData, pagerSettings);
pagerData.EndingPage = GetEndingPage(pagerData, pagerSettings);
// Calculate next page.
if (currentPage + 1 <= pagerData.TotalPages)
{
pagerData.NextPage = currentPage + 1;
}
else
{
pagerData.NextPage = currentPage;
}
// Calculate previous page number.
if (currentPage - 1 >= 1)
{
pagerData.PreviousPage = currentPage - 1;
}
else
{
pagerData.PreviousPage = currentPage;
}
}
/// <summary>
/// Constructor to initialize properties.
/// </summary>
/// <param name="action"></param>
/// <param name="pagerData"></param>
public PagerActionContext(PagerAction action, PagerData pagerData, int newSelectedPage)
{
ActionType = action;
PageData = pagerData;
NewSelectedPage = newSelectedPage;
}
/// <summary>
/// Build the page number links as url links.
/// </summary>
/// <param name="ctx"></param>
/// <param name="settings"></param>
/// <returns></returns>
public string Build(PagerActionContext ctx, PagerSettings settings)
{
PagerData pagerData = ctx.PageData;
// Get reference to the default or custom url builder for this pager.
// A custom url builder may be used for SEO.
PagerUrlBuilder urlBuilder = null;
if (ctx.UrlBuilder == null)
{
urlBuilder = new PagerUrlBuilder(PagerHelper.BuildUrlWithParams);
}
else
{
urlBuilder = ctx.UrlBuilder;
}
StringBuilder buffer = new StringBuilder();
string cssClass = string.Empty;
string urlParams = string.Empty;
string url = ctx.Url;
buffer.Append("<table><tr>");
// Build the previous page link.
if (pagerData.CanShowPrevious)
{
// Previous
url = urlBuilder(ctx.Url, pagerData.CurrentPage - 1);
buffer.Append("<td><span class=\"" + settings.CssClass + "\">");
buffer.Append("<a href=\"" + url + "\">" + "«" + "</a>");
buffer.Append("</span></td>");
}
// Build the starting page link.
if (pagerData.CanShowFirst)
{
// First
url = urlBuilder(ctx.Url, 1);
buffer.Append("<td><span class=\"" + settings.CssClass + "\">");
buffer.Append("<a href=\"" + url + "\">" + 1 + "</a>");
buffer.Append("</span></td>");
// This is to avoid putting ".." between 1 and 2 for example.
// If 1 is the starting page and we want to display 2 as starting page.
if (pagerData.CanShowPrevious)
{
buffer.Append("<td> .. </td>");
}
}
// Each page number.
for (int ndx = pagerData.StartingPage; ndx <= pagerData.EndingPage; ndx++)
{
cssClass = (ndx == pagerData.CurrentPage) ? settings.CssCurrentPage : string.Empty;
url = urlBuilder(ctx.Url, ndx);
// Build page number link. <a href="<%=Url %>" class="<%=cssClass %>" ><%=ndx %></a>
buffer.Append("<td><span class=\"" + settings.CssClass + "\">");
buffer.Append("<a href=\"" + url + "\" class=\"" + cssClass + "\">" + ndx + "</a>");
buffer.Append("</span></td>");
}
// Build the ending page link.
if (pagerData.CanShowLast)
{
url = urlBuilder(ctx.Url, pagerData.TotalPages);
// This is to avoid putting ".." between 7 and 8 for example.
// If 7 is the ending page and we want to display 8 as total pages.
if (pagerData.CanShowNext)
{
buffer.Append("<td> .. </td>");
}
buffer.Append("<td><span class=\"" + settings.CssClass + "\">");
buffer.Append("<a href=\"" + url + "\">" + pagerData.TotalPages + "</a>");
buffer.Append("</span></td>");
}
// Build the next page link.
if (pagerData.CanShowNext)
{
// Previous
url = urlBuilder(ctx.Url, pagerData.CurrentPage + 1);
buffer.Append("<td><span class=\"" + settings.CssClass + "\">");
buffer.Append("<a href=\"" + url + "\">" + "»" + "</a>");
buffer.Append("</span></td>");
}
buffer.Append("</tr></table>");
string content = buffer.ToString();
return(content);
}
/// <summary>
/// Calculate the starting page and ending page.
/// </summary>
/// <param name="pagerData"></param>
/// <param name="pagerSettings"></param>
public static void Calculate(PagerData pagerData, PagerSettings pagerSettings)
{
_instance.Calculate(pagerData, pagerSettings);
}
