C# 异步倒计时
使用C#测试tcp端口连接，我们肯定会想到TcpClient，然后使用tcpclient.Connect()方法，这种方法是可行的，但是有缺陷，是什么呢？使用tcpclient.Connect()方法，程序会等待该方法执行结束后才会继续执行下面的程序段，并且没有超时时间可设置，这样会大大影响程序执行的效率和时间。
如果我们使用tcpclient.BeginConnect()方法，执行效率就会提升很多，并且还可以设置程序超时时间，具体代码如下：
TcpClient tcp = new TcpClient();
var result = tcp.BeginConnect(IP或域名, 端口, null, null);
var sucess = result.AsyncWaitHandle.WaitOne(TimeSpan.FromSeconds(2));
if (!sucess)
{
}
else
{
}
tcp.EndConnect(result);
具体代码就是这样了，实现过程就是获取用于等待异步操作完成的WaitHandle，阻止当前线程，直到当前实例收到信号，同时使用TimeSpan指定时间间隔。
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UIFrame;
using DemoProject;
using UnityEngine.UI;
using System;
using System.Net.NetworkInformation;
using System.Net.Sockets;
using System.IO;
using System.Text;
using Unity.UIWidgets.material;
public class CountDownTimer : MonoBehaviour
{
// 剩余总时间
private int totaltime1 = 5;
private int totaltime2 = 6;
private int totaltime3;
private int totaltime4;
private float intervaletime=1;
// UI倒计时显示文本
public Text countdown1text;
public Text countdown2text;
public Text countdown3text;
public Text countdown4text;
private DateTime dt;
void Start()
{
// UI倒计时显示的格式
countdown1text.text = string.Format("{0:00}:{1:00}", (int)totaltime1 / 60, (float)totaltime1 % 60);
countdown2text.text = string.Format("{0:00}:{1:00}", (int)totaltime2 / 60, (float)totaltime2 % 60);
countdown3text.text = string.Format("{0:00}:{1:00}:{2:00}", 24-(int)totaltime3, 60-((int)totaltime3 / 60), 60-((float)totaltime3 % 60));
countdown4text.text = string.Format("{0:00}:{1:00}:{2:00}", (int)totaltime4/60/60, ((int)totaltime4/60%60), ((int)totaltime4%60));
Debug.Log("开始倒计时迭代器协程");
StartCoroutine(CountDown());
StartCoroutine( LocalTimeControlIE());
StartCoroutine( NetworkTimeControlIE());
}
// 实现倒计时方法一：用IEnumerator协程迭代器
IEnumerator CountDown()
{
while (totaltime1 >=0)
{
int M = (int)(totaltime1 / 60);
float S = totaltime1 % 60;
// 显示格式为 M分：S秒
countdown1text.GetComponent<Text>().text = string.Format("{0:00}:{1:00}", M,S);
// 每一帧update后等待1秒延迟再继续下一帧
yield return new WaitForSeconds(1);
// 时间减去一秒
totaltime1--;
// 计时器复位重新开始计时
if (totaltime1 < 0)
{
totaltime1 = 20;
}
}
}
// 实现倒计时方法二：采用Update方法
// Update is called once per frame
void Update()
{
Debug.Log("开始Update倒计时");
int M = (int)(totaltime2 / 60);
float S = totaltime2 % 60;
if (totaltime2 > 0)
{
intervaletime -= Time.deltaTime;
if (intervaletime <= 0)
{
intervaletime += 1;
totaltime2--;
countdown2text.text = string.Format("{0:00}:{1:00}", M, S);
}
}
if (totaltime2 <= 0)
{
totaltime2 = 20;
}
}
// 获取本地操作系统的时间来倒计时
/// <summary>
/// 计时携程
/// </summary>
/// <returns></returns>
IEnumerator LocalTimeControlIE()
{
while (true)
{
int H = (int)(23 - System.DateTime.Now.Hour);
int M = (int)(60 - System.DateTime.Now.Minute);
int S = (int)(60 - System.DateTime.Now.Second);
countdown3text.text = "本地时间倒计时\n" + string.Format("{0:00}:{1:00}:{2:00}", H, M, S);
yield return new WaitForSeconds(1.0f);
}
}
// Constructor
//public void myMainPage()
//{
// //判断当前网络连接状态
// Network nw = new Network();
// if (nw.IsAvailable)
// lbmsg.Text = "网络已连接";
// else
// lbmsg.Text = "网络已断开";
// //InitializeComponent();
// // Subscribe to the NetworkAvailabilityChanged event
// DeviceNetworkInformation.NetworkAvailabilityChanged += new EventHandler<NetworkNotificationEventArgs>(NetworkAvailabilityChanged);
//}
//void NetworkAvailabilityChanged(object sender, NetworkNotificationEventArgs e)
//{
// string msg = "";
// if (e.IsAvailable)
// {
// msg = "网络已连接";
// }
// else
// {
// msg = "网络已断开";
// }
// Dispatcher.BeginInvoke(() => {
// lbmsg.Text = msg;
// });
//}
// 请求网络时间来倒计时
/// <summary>
/// 计时携程
/// </summary>
/// <returns></returns>
IEnumerator NetworkTimeControlIE()
{
Debug.Log("开始网络倒计时协程");
int nH = 00;
int nM = 00;
int nS = 00;
Debug.Log("开始判断网络连接状态。");
string url = "www.baidu.com;www.sina.com;www.cnblogs.com;www.google.com;www.163.com;www.csdn.com";
string[] urls = url.Split(new char[] { ';' });
if (CheckServeStatus(urls) )
{
Debug.Log(" 侦测到网络连接正常，开始获取网络时间");
nH = (int)DataStandardTime().Hour;
nM = (int)DataStandardTime().Minute;
nS = (int)DataStandardTime().Second;
totaltime4 = 86400 - ((nH * 60 * 60) + (nM * 60) + nS);
}
else
{
Debug.Log(" 侦测到网络连接异常，时间设置为10秒");
totaltime4 =10;
}
while (totaltime4>=1)
{
Debug.Log("开始倒计时");
int H = (int)totaltime4 / 60 / 60;
int M = (int)totaltime4 / 60 % 60;
int S = (int)totaltime4 % 60;
countdown4text.text = "网络时间倒计时\n" + string.Format("{0:00}:{1:00}:{2:00}", H, M, S);
yield return new WaitForSeconds(1.0f);
// 时间减去一秒
totaltime4--;
// 计时器复位重新开始计时
if (totaltime4 < 1)
{
totaltime4 = 86400-((nH * 60 * 60) + (nM*60) + nS);
}
}
}
// 判断网络状态
//public string GetHostNameByIp(string ip)
//{
// ip = ip.Trim();
// if (ip == string.Empty)
// return string.Empty;
// //System.Net.NetworkInformation.Ping pingSender = new System.Net.NetworkInformation.Ping();
// //{
// try
// {
// // 是否 Ping 的通
// if (System.Net.NetworkInformation.Ping(ip))
// {
// System.Net.IPHostEntry host = System.Net.Dns.GetHostEntry(ip);
// return host.HostName;
// }
// else
// return string.Empty;
// }
// catch (Exception)
// {
// return string.Empty;
// }
// //}
//}
/// <summary>
/// 检测网络连接状态
/// </summary>
/// <param name="urls"></param>
//public static void CheckServeStatus(string[] urls)
public bool CheckServeStatus(string[] urls)
{
int errCount = 0;//ping时连接失败个数
//if (!LocalConnectionStatus())
//{
// Console.WriteLine("网络异常~无连接");
//}
if (!MyPing(urls, out errCount))
{
if ((double)errCount / urls.Length >= 0.3)
{
Debug.Log("网络连接异常");
return false;
//Console.WriteLine("网络异常~连接多次无响应");
}
//else
//{
// Console.WriteLine("网络不稳定");
//}
else
{
Debug.Log("网络连接正常");
return true;
}
}
else
{
Debug.Log("网络连接正常");
return true;
//Console.WriteLine("网络正常");
}
}
/// <summary>
/// Ping命令检测网络是否畅通
/// </summary>
/// <param name="urls">URL数据</param>
/// <param name="errorCount">ping时连接失败个数</param>
/// <returns></returns>
public static bool MyPing(string[] urls, out int errorCount)
{
bool isconnected = true;
System.Net.NetworkInformation.Ping ping = new System.Net.NetworkInformation.Ping();
errorCount = 0;
try
{
PingReply pr;
for (int i = 0; i < urls.Length; i++)
{
pr = ping.Send(urls[i]);
if (pr.Status != IPStatus.Success)
{
isconnected = false;
errorCount++;
}
Console.WriteLine("Ping " + urls[i] + " " + pr.Status.ToString());
}
}
catch
{
isconnected = false;
errorCount = urls.Length;
}
//if (errorCount > 0 && errorCount < 3)
// isconn = true;
return isconnected;
}
//public static DateTime DataStandardTime()//使用时，将static 关键字删除，在其它位置方可使用
public DateTime DataStandardTime()//使用时，将static 关键字删除，在其它位置方可使用
{//返回国际标准时间
//只使用的TimerServer的IP地址，未使用域名
string[,] TimerServer = new string[14, 2];
int[] ServerTab = new int[] { 3, 2, 4, 8, 9, 6, 11, 5, 10, 0, 1, 7, 12 };
TimerServer[0, 0] = "time-a.nist.gov";
TimerServer[0, 1] = "129.6.15.28";
TimerServer[1, 0] = "time-b.nist.gov";
TimerServer[1, 1] = "129.6.15.29";
TimerServer[2, 0] = "time-a.timefreq.bldrdoc.gov";
TimerServer[2, 1] = "132.163.4.101";
TimerServer[3, 0] = "time-b.timefreq.bldrdoc.gov";
TimerServer[3, 1] = "132.163.4.102";
TimerServer[4, 0] = "time-c.timefreq.bldrdoc.gov";
TimerServer[4, 1] = "132.163.4.103";
TimerServer[5, 0] = "utcnist.colorado.edu";
TimerServer[5, 1] = "128.138.140.44";
TimerServer[6, 0] = "time.nist.gov";
TimerServer[6, 1] = "192.43.244.18";
TimerServer[7, 0] = "time-nw.nist.gov";
TimerServer[7, 1] = "131.107.1.10";
TimerServer[8, 0] = "nist1.symmetricom.com";
TimerServer[8, 1] = "69.25.96.13";
TimerServer[9, 0] = "nist1-dc.glassey.com";
TimerServer[9, 1] = "216.200.93.8";
TimerServer[10, 0] = "nist1-ny.glassey.com";
TimerServer[10, 1] = "208.184.49.9";
TimerServer[11, 0] = "nist1-sj.glassey.com";
TimerServer[11, 1] = "207.126.98.204";
TimerServer[12, 0] = "nist1.aol-ca.truetime.com";
TimerServer[12, 1] = "207.200.81.113";
TimerServer[13, 0] = "nist1.aol-va.truetime.com";
TimerServer[13, 1] = "64.236.96.53";
int portNum = 13;
string hostName;
byte[] bytes = new byte[1024];
int bytesRead = 0;
string strResponse = null;
string str2 = null;
System.Net.Sockets.TcpClient client = new System.Net.Sockets.TcpClient();
for (int i = 0; i < 13; i++)
{
hostName = TimerServer[ServerTab[i], 0];
Debug.Log("开始请求远端服务器 hostName:" + hostName);
try
{
// 同步连接服务器
// client.Connect(hostName, portNum);
// 异步连接服务器
// client.BeginConnect(hostName, Convert.ToInt32(portNum), new AsyncCallback(ConnectCallback),client);
Debug.Log("开始异步连接服务器");
var connectResult = client.BeginConnect(hostName, portNum, null, null);
var connectOK = connectResult.AsyncWaitHandle.WaitOne(TimeSpan.FromSeconds(1));
Debug.Log("连接服务器状态："+connectOK);
if (!connectOK)
{
Debug.Log("网络未连接");
client.Close();
break;
}
else
{
System.Net.Sockets.NetworkStream ns = client.GetStream();
Debug.Log("开始获取网络字节流："+ns);
// 同步读取
//if (ns.CanRead)
//{
// bytesRead = ns.Read(bytes, 0, bytes.Length);
// client.Close();
// ns.Close();
// break;
//}
//else
//{
// client.Close();
// ns.Close();
// Debug.Log("网络错误！");
// break;
//}
// 异步读取
try
{
byte[] result = new byte[client.Available];
ns.BeginRead(result, 0, result.Length, new AsyncCallback(MyReadCallback), ns);
Debug.Log("开始异步接收网络数据："+ns);
strResponse = Encoding.ASCII.GetString(result).Trim();
Debug.Log("得到异步接收的网络数据 strResponse ntp time:" +strResponse);
str2 = strResponse;
client.Close();
break;
}
catch
{
Debug.Log("网络错误！");
}
}
// client.EndConnect(connectResult);
MyConnectCallback(connectResult);
}
catch (System.Exception)
{
Debug.Log("获取错误！");
}
}
Debug.Log("得到 ntp time:" + str2);
if (str2 != null)
{
char[] sp = new char[1];
sp[0] = ' ';
System.DateTime dt = new DateTime();
//string str1;
//str2 = System.Text.Encoding.ASCII.GetString(bytes, 0, bytesRead);
str2 = str2.Replace("PDT", "");
string[] s;
//s = str1.Split(sp);
s = str2.Split(sp);
// "58961 20-04-22 07:22:32 50 0 0 900.6 UTC(NIST) *"
dt = System.DateTime.Parse(s[1] + " " + s[2]);//得到标准时间
//Debug.WriteLine("get:" + dt.ToShortTimeString());
Debug.Log("得到标准时间:" + dt.ToShortTimeString());
//dt=dt.AddHours (8);
dt = dt.ToLocalTime();
Debug.Log("得到本地时间:" + dt);
return dt;
}
else
{
dt = System.DateTime.Parse("20200000000000");
Debug.Log(" 获取网络时间失败，已经获取到本机系统时间.");
return dt;
}
}
private static void MyReadCallback(IAsyncResult iar)
{
//
NetworkStream ns = (NetworkStream)iar.AsyncState;
byte[] read = new byte[1024];
String data = "";
int recv;
recv = ns.EndRead(iar);
data = String.Concat(data, Encoding.ASCII.GetString(read, 0, recv));
//接收到的消息长度可能大于缓冲区总大小，反复循环直到读完为止
while (ns.DataAvailable)
{
ns.BeginRead(read, 0, read.Length, new AsyncCallback(MyReadCallback), ns);
}
//打印
Console.WriteLine("您收到的信息是" + data);
Debug.Log("您收到的信息是" + data);
}
private void MyConnectCallback(IAsyncResult ar)
{
TcpClient t = (TcpClient)ar.AsyncState;
try
{
if (t.Connected)
{
t.EndConnect(ar);//函数运行到这里就说明连接成功
}
else
{
}
}
catch
{ }
}
}