Get network time by unity

Network time

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Networking;

public class NetworkTime : MonoBehaviour
{
        
    void Start()
    {
    
    	//  Automatically get network time 
        StartCoroutine(GetWebTime());
    }

    #region  Get network time 

    /// <summary>
    ///  Get the current network time 
    /// </summary>
    /// <returns></returns>
    IEnumerator GetWebTime()
    {
    
        //  Get time address 
        string url = "https://www.baidu.com"; //  Baidu  //http://www.beijing-time.org/"; //  Beijing time. 
        Debug.Log(" Start getting server time ...  The access address is : " + url);

        DateTime _webNowTime = DateTime.Now;
        //  Acquisition time 
        UnityWebRequest WebRequest = new UnityWebRequest(url);

        //  Wait for the request to complete 
        yield return WebRequest.SendWebRequest();
        
        // Page loading complete   And there are no errors in the download process  string.IsNullOrEmpty  Determine whether the string is null  Or is it " ", If it's a return true
        //WebRequest.error  If a download error occurs during the download process   Will return an error message   If the download is not completed, it will be blocked until the download is completed 
        if (WebRequest.isDone && string.IsNullOrEmpty(WebRequest.error))
        {
    
        	//  Save the return value as a dictionary 
            Dictionary<string, string> resHeaders = WebRequest.GetResponseHeaders();
            string key = "DATE";
            string value = null;
            //  obtain key by "DATE"  Of  Value value 
            if (resHeaders != null && resHeaders.ContainsKey(key))
            {
    
                resHeaders.TryGetValue(key, out value);
            }

            if (value == null)
            {
    
                Debug.LogError(" No access to key by DATE Corresponding Value value ...");
                yield break;
            }

            //  Here we are value, Convert to local time 
            _webNowTime = FormattingGMT(value);
            Debug.Log(value + " , Network time after conversion ：" + _webNowTime);

            //  Convert to timestamp 
            TimeSpan cha = (_webNowTime - TimeZone.CurrentTimeZone.ToLocalTime(new DateTime(1970, 1, 1)));
            long t = (long) cha.TotalSeconds;
            Debug.Log(" Network time to timestamp ：" + t);
        }
    }

    /// <summary>
    /// GMT( Greenwich mean time ) Convert time to local time 
    /// </summary>
    /// <param name="gmt"> In string form GMT Time </param>
    /// <returns></returns>
    private DateTime FormattingGMT(string gmt)
    {
    
        DateTime dt = DateTime.MinValue;
        try
        {
    
            string pattern = "";
            if (gmt.IndexOf("+0") != -1)
            {
    
                gmt = gmt.Replace("GMT", "");
                pattern = "ddd, dd MMM yyyy HH':'mm':'ss zzz";
            }

            if (gmt.ToUpper().IndexOf("GMT") != -1)
            {
    
                pattern = "ddd, dd MMM yyyy HH':'mm':'ss 'GMT'";
            }

            if (pattern != "")
            {
    
                dt = DateTime.ParseExact(gmt, pattern, System.Globalization.CultureInfo.InvariantCulture,
                    System.Globalization.DateTimeStyles.AdjustToUniversal);
                dt = dt.ToLocalTime();
            }
            else
            {
    
                dt = Convert.ToDateTime(gmt);
            }
        }
        catch (Exception e)
        {
    
            Debug.Log(e);
            Debug.LogError(" Time conversion error ...");
        }
        return dt;
    }
    #endregion
}