Inorder traversal of binary tree with recursion in typescript

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

/* 
  TypeScript Program for
  inorder tree traversal of a Binary Tree
  using recursion
*/
// Binary Tree Node
class TreeNode
{
	public data: number;
	public left: TreeNode;
	public right: TreeNode;
	constructor(data: number)
	{
		// Set node value
		this.data = data;
		this.left = null;
		this.right = null;
	}
}
class BinaryTree
{
	public root: TreeNode;
	constructor()
	{
		// Set initial tree root
		this.root = null;
	}
	// Display Inorder view of binary tree
	public inorder(node: TreeNode)
	{
		if (node != null)
		{
			// Visit left subtree
			this.inorder(node.left);
			//Print node value
			console.log("  " + node.data);
			// Visit right subtree
			this.inorder(node.right);
		}
	}
	public static main(args: string[])
	{
		// 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);
	}
}
BinaryTree.main([]);
/*
 file : code.ts
 tsc --target es6 code.ts
 node code.js
 */

Output

  35
  24
  15
  62
  54
  13