网络时间获取

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Net;

namespace 时间
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            timer1.Interval = 1000;
            timer1.Start();
        }
        private void rftime()
        {
            DateTime dt = DateTime.Now;
            String date = dt.ToLongDateString();
            String time = dt.ToLongTimeString();


        }

        private void timer1_Tick(object sender, EventArgs e)
        {
            {//显示时间
                string netTime = GetNetDateTime();
                if (netTime != "")
                {
                    LabNow.Text = "北京时间（网络）：" + Convert.ToDateTime(netTime).ToString("yyyy年MM月dd dddd HH时mm分ss秒");
                }
                else
                {
                    LabNow.Text = "北京时间（本地）：" + DateTime.Now.ToString("yyyy年MM月dd dddd HH时mm分ss秒");
                }


            }
        }
        public static string GetNetDateTime()
        {//获取网络时间
            WebRequest request = null;
            WebResponse response = null;
            WebHeaderCollection headerCollection = null;
            string datetime = string.Empty;
            try
            {
                request = WebRequest.Create("https://www.baidu.com");
                request.Timeout = 3000;
                request.Credentials = CredentialCache.DefaultCredentials;
                response = request.GetResponse();
                headerCollection = response.Headers;
                foreach (var h in headerCollection.AllKeys)
                {
                    if (h == "Date")
                    {
                        datetime = headerCollection[h];
                    }
                }
                return datetime;
            }
            catch (Exception) { return datetime; }
            finally
            {
                if (request != null)
                { request.Abort(); }
                if (response != null)
                { response.Close(); }
                if (headerCollection != null)
                { headerCollection.Clear(); }
            }
        }
    }
}