I have looked through a few SQL hierarchy tutorials, but none of them made much sense for my application. Perhaps I am just not understanding them correctly. I'm writing a C# ASP.NET application and I would like to create a tree view hierarchy from SQL data.
This is how the hierarchy would work:
SQL TABLE ID | Location ID | Name _______| __________ |_____________ 1331 | 1331 | House 1321 | 1331 | Room 2141 | 1321 | Bed 1251 | 2231 | Gym
If the ID and Location ID are the same, this would determine the top Parent. Any Children of that Parent would have the same Location ID as the Parent. Any Grandchildren of that Child would have a Location ID equal to the ID of the Child, and so on.
For the above example:
- House -- Room --- Bed
Any help or direction to easy to follow tutorials would be greatly appreciated.
EDIT:
Code I have so far, but it only gets the Parent and Children, no GrandChildren. I can't seem to figure out how to get it to recursively get all of the nodes.
using System;
using System.Data;
using System.Collections.Generic;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Configuration;
using System.Data.SqlClient;
namespace TreeViewProject
{
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
PopulateTree(SampleTreeView);
}
public void PopulateTree(Control ctl)
{
// Data Connection
SqlConnection connection = new SqlConnection(ConfigurationManager.ConnectionStrings["AssetWhereConnectionString1"].ConnectionString);
connection.Open();
// SQL Commands
string getLocations = "SELECT ID, LocationID, Name FROM dbo.Locations";
SqlDataAdapter adapter = new SqlDataAdapter(getLocations, connection);
DataTable locations = new DataTable();
// Fill Data Table with SQL Locations Table
adapter.Fill(locations);
// Setup a row index
DataRow[] myRows;
myRows = locations.Select();
// Create an instance of the tree
TreeView t1 = new TreeView();
// Assign the tree to the control
t1 = (TreeView)ctl;
// Clear any exisiting nodes
t1.Nodes.Clear();
// BUILD THE TREE!
for (int p = 0; p < myRows.Length; p++)
{
// Get Parent Node
if ((Guid)myRows[p]["ID"] == (Guid)myRows[p]["LocationID"])
{
// Create Parent Node
TreeNode parentNode = new TreeNode();
parentNode.Text = (string)myRows[p]["Name"];
t1.Nodes.Add(parentNode);
// Get Child Node
for (int c = 0; c < myRows.Length; c++)
{
if ((Guid)myRows[p]["LocationID"] == (Guid)myRows[c]["LocationID"]
&& (Guid)myRows[p]["LocationID"] != (Guid)myRows[c]["ID"] /* Exclude Parent */)
{
// Create Child Node
TreeNode childNode = new TreeNode();
childNode.Text = (string)myRows[c]["Name"];
parentNode.ChildNodes.Add(childNode);
}
}
}
}
// ALL DONE BUILDING!
// Close the Data Connection
connection.Close();
}
}
}
Here is a snippit from the actual SQL table: Locations
ID LocationID Name ____________________________________ ____________________________________ ______________ DEAF3FFF-FD33-4ECF-910B-1B07DF192074 48700BC6-D422-4B26-B123-31A7CB704B97 Drop F 48700BC6-D422-4B26-B123-31A7CB704B97 7EBDF61C-3425-46DB-A4D5-686E91FD0832 Olway 06B49351-6D18-4595-8228-356253CF45FF 6E8C65AC-CB22-42DA-89EB-D81C5ED0BBD0 Drop E 5 E98BC1F6-4BAE-4022-86A5-43BBEE2BA6CD DEAF3FFF-FD33-4ECF-910B-1B07DF192074 Drop F 6 F6A2CF99-F708-4C61-8154-4C04A38ADDC6 7EBDF61C-3425-46DB-A4D5-686E91FD0832 Pree 0EC89A67-D74A-4A3B-8E03-4E7AAAFEBE51 6E8C65AC-CB22-42DA-89EB-D81C5ED0BBD0 Drop E 4 35540B7A-62F9-487F-B65B-4EA5F42AD88A 48700BC6-D422-4B26-B123-31A7CB704B97 Olway Breakdown 5000AB9D-EB95-48E3-B5C0-547F5DA06FC6 6E8C65AC-CB22-42DA-89EB-D81C5ED0BBD0 Out 1 53CDD540-19BC-4BC2-8612-5C0663B7FDA5 6E8C65AC-CB22-42DA-89EB-D81C5ED0BBD0 Drop E 3 7EBDF61C-3425-46DB-A4D5-686E91FD0821 B46C7305-18B1-4499-9E1C-7B6FDE786CD6 TEST 1 7EBDF61C-3425-46DB-A4D5-686E91FD0832 7EBDF61C-3425-46DB-A4D5-686E91FD0832 HMN
Thanks.