public void StepTo(Pager pager, PagingItemInfo pagingItem)
{
Argument.IsNotNull(() => pager);
var stepValue = pagingItem.StepValue;
Step(pager, stepValue);
}
public void MoveToLast(Pager pager)
{
Argument.IsNotNull(() => pager);
pager.ItemIndex = GetLastPageIndex(pager);
;
}
public void MoveToFirst(Pager pager)
{
Argument.IsNotNull(() => pager);
if (pager.ItemIndex == 0)
{
return;
}
pager.ItemIndex = 0;
}
public void Step(Pager pager, int stepValue)
{
Argument.IsNotNull(() => pager);
var newIndex = pager.ItemIndex + pager.ItemsPerPage*stepValue;
if (newIndex < 0)
{
newIndex = 0;
}
pager.ItemIndex = newIndex;
}
public void UpdatePagingItems(Pager pager)
{
Argument.IsNotNull(() => pager);
if (pager.ItemsPerPage == 0)
{
return;
}
int leftPages;
int rightPages;
var currentPage = GetPagesCount(pager, out leftPages, out rightPages);
FillLeftPages(pager, leftPages, currentPage);
FillRightPages(pager, rightPages, currentPage);
}
private int GetPagesCount(Pager pager, out int leftPages, out int rightPages)
{
Argument.IsNotNull(() => pager);
leftPages = 0;
rightPages = 0;
var rightItems = pager.ItemsCount - pager.ItemIndex;
var leftItems = pager.ItemsCount - rightItems;
var totalRightPages = (int) Math.Ceiling(rightItems/(double) pager.ItemsPerPage) - 1;
var totalLeftPages = (int) Math.Ceiling(leftItems/(double) pager.ItemsPerPage);
var totalPagesCount = totalRightPages + totalLeftPages;
var currentPage = totalLeftPages + 1;
pager.CurrentPage = currentPage.ToString(CultureInfo.InvariantCulture);
var leftAdding = true;
var pageCouner = 0;
while (pageCouner < pager.VisiblePages - 1 && pageCouner < totalPagesCount)
{
if (totalLeftPages.Equals(0))
{
leftAdding = false;
}
if (totalRightPages.Equals(0))
{
leftAdding = true;
}
if (totalLeftPages > 0 && leftAdding)
{
leftAdding = false;
leftPages++;
totalLeftPages--;
pageCouner++;
continue;
}
if (totalRightPages > 0 && !leftAdding)
{
leftAdding = true;
rightPages++;
totalRightPages--;
pageCouner++;
}
}
return currentPage;
}
private static int GetLastPageIndex(Pager pager)
{
var pagesCount = (int) Math.Ceiling(pager.ItemsCount/(double) pager.ItemsPerPage);
var i = (pagesCount - 1)*pager.ItemsPerPage;
return i;
}
public bool IsLastPage(Pager pager)
{
var lastPageIndex = GetLastPageIndex(pager);
return pager.ItemIndex >= lastPageIndex;
}
private void FillLeftPages(Pager pager, int leftPagesCount, int currentPage)
{
Argument.IsNotNull(() => pager);
pager.LeftPages.Clear();
for (var i = leftPagesCount; i > 0; i--)
{
pager.LeftPages.Add(new PagingItemInfo((currentPage - i).ToString(CultureInfo.InvariantCulture), -1*i));
}
}
private void FillRightPages(Pager pager, int rightPages, int currentPage)
{
Argument.IsNotNull(() => pager);
pager.RightPages.Clear();
for (var i = 1; i <= rightPages; i++)
{
pager.RightPages.Add(new PagingItemInfo((currentPage + i).ToString(CultureInfo.InvariantCulture), i));
}
}