/// <summary>
/// 将关系数据列表 转化为 树状图
/// </summary>
/// <param name="parentId">根节点</param>
/// <param name="relation">关系数据</param>
/// <returns></returns>
public Node GetRoot(int parentId, List<Mapping> mapping)
{
var root = new Node();
root.Key = parentId;
var groups = mapping.Select(x => new Node { Key = x.ChildID, Left = x.ParentID }).GroupBy(x => x.Left);
var child = groups.FirstOrDefault(x => x.Key == parentId);
if (child == null)
{
return null;
}
else
{
var children = child.ToList();
if (children.Count > 0)
{
var dict = groups.ToDictionary(g => g.Key, g => g.ToList());
for (int i = 0; i < children.Count; i++)
{
this.AddChild(children[i], dict);
}
}
root.Children = children;
}
return root;
}
public void AddChild(Node child, IDictionary<int, List<Node>> mapping)
{
if (mapping != null && mapping.ContainsKey(child.Key))
{
child.Children = mapping[child.Key].ToList();
for (int i = 0; i < child.Children.Count; i++)
{
this.AddChild(child.Children[i], mapping);
}
}
}
public void PrintTree(Node node, string prefix)
{
Console.WriteLine("{0} + {1}", prefix, node.Key);
if (node.Children == null)
{
return;
}
foreach (Node child in node.Children)
{
PrintTree(child, prefix + " |");
}
}
