Correct my c# program.

[baran]

Hi
please correct program Binary Tree

 class TreeNode
    {
        private int dataValue;
        private TreeNode leftNode = null;
        private TreeNode rightNode = null;
 
        public TreeNode(int data)
        {
            dataValue = data;
        }
        public TreeNode LeftNode
        {
            get
            {
                return leftNode;
            }
            set
            {
                leftNode = value;
            }
        }
        public TreeNode RightNode
        {
            get
            {
                return rightNode;
            }
            set
            {
                rightNode = value;
            }
        }
        public int DataValue
        {
            get
            {
                return dataValue;
            }
            set
            {
                dataValue = value;
            }
        }
 
 

Eror is root null.

class Program
    {
 
 
        static void Main(string[] args)
        {
 
            Tree node = new Tree();
            TreeNode T = new TreeNode(0);
            create(T, 1);
            Console.WriteLine();
            Console.ReadLine();
        }
        public TreeNode create(TreeNode root, int dataValue)
        {
 
            if (root == null)
            {
                if (root == null)
                { return null; }
                else if (root.DataValue == dataValue)
                { return root; }
                else if (root.DataValue < dataValue)
                { return create(root.RightNode, dataValue); }
                else
                {
                    return create(root.LeftNode, dataValue);
                }
 
            }
 
        }
    }