三种方式实现递归树加载

1、数据库实现：

可以将此段数据库代码修改为存储过程实现：

with temp
as
(SELECT * FROM EKP_Module WHERE mod_parentid = 2165
UNION ALL
SELECT m.* FROM EKP_Module AS m
INNER JOIN temp AS child ON m.mod_parentid = child.mod_id
)

select * from temp

2、Linq to Sql实现：

public IEnumerable<APPModuleInfo> GetModulesByPID(int p_id)
{
IQueryable<APPModuleInfo> mods = from m in ekpEntities.EKP_MODULE
where m.mod_parentid == p_id
select new APPModuleInfo
{
ModId = m.mod_id,
ModLink = m.ModLink,
ModName = m.mod_name,
ModParentId = m.mod_parentid
};

return mods.ToList().Concat(mods.ToList().SelectMany(m => GetModulesByPID(m.ModId)));
}

3、常规方式实现：

public void AddTree(string ParentID, TreeNode pNode)
    {
        if (ds.Tables.Count > 0)
        {
            DataView dvTree = new DataView(ds.Tables[0]);
            //过滤ParentOrgID,得到当前的所有子节点   
            dvTree.RowFilter = "[IndexParentID]   =   '" + ParentID + "' and [StatusFlag]='1'";
            foreach (DataRowView Row in dvTree)
            {
                TreeNode node = new TreeNode();
                if (pNode == null)
                {         //添加根节点   
                    node.Text = Row["IndexName"].ToString();
                    node.Value = Row["IndexID"].ToString();
                    TreeView1.Nodes.Add(node);
                    AddTree(Row["IndexID"].ToString(), node);         //再次递归   
                }
                else
                {       //添加当前节点的子节点   
                    node.Text = Row["IndexName"].ToString();
                    node.Value = Row["IndexID"].ToString();
                    pNode.ChildNodes.Add(node);
                    AddTree(Row["IndexID"].ToString(), node);         //再次递归   
                }
            }
            dvTree.Dispose();
            ds.Dispose();
        }

    }