一个创建无限递归树的帮助类(C#)——几乎每个系统都用的上
/// <summary> /// 树结构帮助类 /// </summary> public class TreeHelper { /// <summary> /// 建造树结构 /// </summary> /// <param name="allNodes">所有的节点</param> /// <returns></returns> public static List<T> BuildTree<T>(List<T> allNodes) where T : TreeModel, new() { List<T> resData = new List<T>(); var rootNodes = allNodes.Where(x => x.ParentId == "0" || x.ParentId.IsNullOrEmpty()).ToList(); resData = rootNodes; resData.ForEach(aRootNode => { if (HaveChildren(allNodes, aRootNode.Id)) aRootNode.Children = GetChildren(allNodes, aRootNode); }); return resData; } /// <summary> /// 获取所有子节点 /// </summary> /// <typeparam name="T">树模型(TreeModel或继承它的模型)</typeparam> /// <param name="nodes">所有节点列表</param> /// <param name="parentNode">父节点Id</param> /// <returns></returns> private static List<object> GetChildren<T>(List<T> nodes, T parentNode) where T : TreeModel, new() { Type type = typeof(T); var properties = type.GetProperties().ToList(); List<object> resData = new List<object>(); var children = nodes.Where(x => x.ParentId == parentNode.Id).ToList(); children.ForEach(aChildren => { T newNode = new T(); resData.Add(newNode); //赋值属性 properties.ForEach(aProperty => { var value = aProperty.GetValue(aChildren, null); aProperty.SetValue(newNode, value); }); //设置深度 newNode.Level = parentNode.Level + 1; if (HaveChildren(nodes, aChildren.Id)) newNode.Children = GetChildren(nodes, newNode); }); return resData; } /// <summary> /// 判断当前节点是否有子节点 /// </summary> /// <typeparam name="T">树模型</typeparam> /// <param name="nodes">所有节点</param> /// <param name="nodeId">当前节点Id</param> /// <returns></returns> private static bool HaveChildren<T>(List<T> nodes, string nodeId) where T : TreeModel, new() { return nodes.Exists(x => x.ParentId == nodeId); } }