Inorder traversal of binary tree with recursion in c#

Csharp program for Inorder traversal of binary tree with recursion. Here problem description and explanation.

// Include namespace system
using System;
/* 
  Csharp Program for
  inorder tree traversal of a Binary Tree
  using recursion
*/
// Binary Tree Node
public class TreeNode
{
	public int data;
	public TreeNode left;
	public TreeNode right;
	public TreeNode(int data)
	{
		// Set node value
		this.data = data;
		this.left = null;
		this.right = null;
	}
}
public class BinaryTree
{
	public TreeNode root;
	public BinaryTree()
	{
		// Set initial tree root
		this.root = null;
	}
	// Display Inorder view of binary tree
	public void inorder(TreeNode node)
	{
		if (node != null)
		{
			// Visit left subtree
			this.inorder(node.left);
			//Print node value
			Console.Write("  " + node.data.ToString());
			// Visit right subtree
			this.inorder(node.right);
		}
	}
	public static void Main(String[] args)
	{
		// Create new tree
		var tree = new BinaryTree();
		/*
		    Make A Binary Tree
		    ----------------
		        15
		       /  \
		      24   54
		     /    /  \
		    35   62   13
		*/
		// Add tree TreeNode
		tree.root = new TreeNode(15);
		tree.root.left = new TreeNode(24);
		tree.root.right = new TreeNode(54);
		tree.root.right.right = new TreeNode(13);
		tree.root.right.left = new TreeNode(62);
		tree.root.left.left = new TreeNode(35);
		// Display Tree Node
		tree.inorder(tree.root);
	}
}

Output

  35  24  15  62  54  13