//-----------------------------------------------------
// Builds a hierarchical tree out of a List<HierarchyTable>
// and copies each child row into a different
// List<HierarchyTable> as it is being built.
//-----------------------------------------------------
public static List <HierarchyTable> HierarchicalSort(ICollection <HierarchyTable> inputlist)
{
HierarchyTable topNode = inputlist.ElementAt(0);
HierarchyTable current = topNode;
HierarchyTable child = null;
inputlist.Remove(topNode);
List <HierarchyTable> copyList = inputlist.Take(inputlist.Count).ToList();
List <HierarchyTable> outputList = new List <HierarchyTable>()
{
topNode
};
foreach (HierarchyTable rec in inputlist)
{
do
{
child = GetNextNode(current, copyList);
if (child != null)
{
child.Parent = current;
current.Children.Add(child);
current = child;
copyList.Remove(child);
outputList.Add(child);
}
} while (child != null);
current = topNode;
}
return(outputList);
}
//-----------------------------------------------------
// Returns the first child of a sorted match on
// ID == ParentID. If you end up needing to sort on
// multiple columns or objects that don't already
// implement IComparer, then make your own comparer
// class. The syntax would be:
//
// .OrderBy(x => x, new ComparerClass());
//-----------------------------------------------------
private static HierarchyTable GetNextNode(HierarchyTable current, ICollection <HierarchyTable> inputlist)
{
List <HierarchyTable> sublist = inputlist
.Where(
a => a.ParentID == current.ID
).OrderBy(
x => x.SortOrder
).ToList();
if (sublist.Count > 0)
{
return(sublist.First());
}
return(null);
}
public HierarchyTable(HierarchyTable parent)
{
Parent = parent;
Children = new List <HierarchyTable>();
}
