距离某天还有多久

using UnityEngine;
using System.Collections;
using System;

public class test : MonoBehaviour {
DateTime dt1;
DateTime dt2;
TimeSpan ts;
public GameObject mObj;
private UILabel mLab;
// Use this for initialization
void Start () {

dt2 = new DateTime(2014,1,18);
mLab = mObj.GetComponent<UILabel>();
}

// Update is called once per frame
void Update () {
dt1 = DateTime.Now;
ts = dt1.Subtract(dt2);
mLab.text = ts.ToString();
Debug.Log(ts);
}
}