private void BuildLinkedList()
{
var count = 0;
var lookup = _pageIndex.ToLookup(i => i.ParentId, i => count++);
foreach (var page in _pageIndex)
{
var pageId = page.PageId;
var childId = 0;
foreach (var index in lookup[pageId])
{
if (childId == 0)
{
page.FirstChild = index;
}
else
{
_pageIndex[childId].NextPage = index;
}
childId = index;
}
}
}
