Reconnection based client TCP communications
Reprinted: http://www.cnblogs.com/networkcomms/p/4304362.html
In the CS program, the reconnection should be a common feature.
Disconnection reconnection here mainly refers to the server because of a certain failure, the server program or the system is rebooted, the client can automatically detect the server take away line, and try to reconnect
This procedure based on networkcomms c # open communication frame from the UK (version 2.3.1)
Look at the results
Initial state:
When the server program is closed, the client automatically detects and displays the information in the client
Then, we set every five seconds reconnection time, the number of times you can customize settings for reconnection, for example, reconnect 50 times, if it is not successful reconnection, the reconnection give up
Then we restart the server, the client will show reconnection.
Specific steps are as follows:
Require code several communication frame NetworkComms2.3.1
The first step: Modify NoteConnectionShutdown method ConnectionInfo class
This method turned out to be:
internal void NoteConnectionShutdown()
{
lock (internalLocker)
ConnectionState = ConnectionState.Shutdown;
}
After amended as follows:
private bool reconnectFlag = false;
/// <summary>
/// 是否为重连接模式
/// </summary>
public bool ReconnectFlag
{
get { return reconnectFlag; }
set { reconnectFlag = value; }
}
/// <summary>
/// Note this connection as shutdown
/// </summary>
internal void NoteConnectionShutdown()
{
lock (internalLocker)
ConnectionState = ConnectionState.Shutdown;
//添加以下代码 初始状态为False 触发连接状态改变事件
if (reconnectFlag == false)
{
StateChanged.Raise(this, new StringEventArgs("连接出现异常"));
}
}
//添加状态改变事件
public event EventHandler<StringEventArgs> StateChanged;
第二步：在NetworkComms库类中添加相关的代码如下：
using System;
using System.Collections.Generic;
using System.Text;
using NetworkCommsDotNet.Tools;
namespace NetworkCommsDotNet
{
public static class Extensions
{
public static void Raise<T>(this EventHandler<T> handler, object sender, T args) where T : EventArgs
{
if (handler != null)
handler(sender, args);
}
}
public class StringEventArgs : EventArgs
{
public StringEventArgs(string text)
{
Text = text;
}
public string Text { get; set; }
}
}
namespace System.Runtime.CompilerServices
{
[AttributeUsage(AttributeTargets.Method | AttributeTargets.Class | AttributeTargets.Assembly)]
public sealed class ExtensionAttribute : Attribute { }
}
第三步：在NetworkComms静态类中添加如下方法：
public static void ClearDic()
{
lock (globalDictAndDelegateLocker)
{
allConnectionsById.Clear();
allConnectionsByEndPoint.Clear();
oldNetworkIdentifierToConnectionInfo.Clear();
}
}
如果您使用的是V3版本，代码稍微变化：
public static void ClearDic()
{
lock (globalDictAndDelegateLocker)
{
allConnectionsByIdentifier.Clear();
allConnectionsByEndPoint.Clear();
oldNetworkIdentifierToConnectionInfo.Clear();
}
}
客户端代码：
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using NetworkCommsDotNet;
using DPSBase;
using System.Net;
using System.Threading;
namespace AppClient
{
public partial class Form1 : Form
{
//连接信息类
public ConnectionInfo connnectionInfo = null;
//连接类
Connection connection;
public Form1()
{
InitializeComponent();
}
//在窗体上显示新信息
void Form_ConnectionStatusNotify(object sender, StringEventArgs e)
{
if (this.InvokeRequired)
{
this.Invoke(new EventHandler<StringEventArgs>(this.Form_ConnectionStatusNotify), sender, e);
}
else
{
lblLink.Text = e.Text;
lblLink.ForeColor = Color.Blue;
}
}
private bool ServerNotifyClose = false;
public event EventHandler<StringEventArgs> ConnectionStatusNotify;
void connnectionInfo_StateChanged(object sender, StringEventArgs e)
{
//如果不是服务器通知关闭，则自动重连，如果是服务器通知关闭，则不作处理
//本Demo中没有使用ServerNotifyClose
if (ServerNotifyClose == false)
{
//更新连接信息类 设置为重连模式
connnectionInfo.ReconnectFlag = true;
ConnectionStatusNotify.Raise(this, new StringEventArgs("可能由于服务器的故障，与服务器端的连接已断开"));
int num = 0;
int retryCount = 30;
int retrySpanInMSecs = 5000;
do
{
try
{
NetworkComms.ClearDic();
connection = TCPConnection.GetConnection(connnectionInfo);
ConnectionStatusNotify.Raise(this, new StringEventArgs("重连成功"));
connnectionInfo.ReconnectFlag = false;
break;
}
catch (Exception ex)
{
num++;
if (num < retryCount)
{
ConnectionStatusNotify.Raise(this, new StringEventArgs("正在进行第" + num + "次重连"));
Thread.Sleep(retrySpanInMSecs);
}
}
}
while (num < retryCount);
}
}
private void button1_Click(object sender, EventArgs e)
{
connnectionInfo = new ConnectionInfo(txtIP.Text, int.Parse(txtPort.Text));
//如果不成功，会弹出异常信息
connection = TCPConnection.GetConnection(connnectionInfo);
button1.Enabled = false;
button1.Text = "连接成功";
//订阅连接信息类中的连接状态改变事件
connnectionInfo.StateChanged += new EventHandler<StringEventArgs>(connnectionInfo_StateChanged);
this.ConnectionStatusNotify += new EventHandler<StringEventArgs>(Form_ConnectionStatusNotify);
}
//获取水果相关信息
private void button2_Click(object sender, EventArgs e)
{
if (listBox1.SelectedIndex > -1)
{
string resMsg = connection.SendReceiveObject<string>("ReqFruitEngName", "ResFruitEngName", 5000, listBox1.Text);
MessageBox.Show("您选择的水果的英文名称是：" + resMsg);
}
else
{
MessageBox.Show("请选择一项");
}
}
private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
this.Dispose();
}
}
}
服务器端无需额外的设置。
转载：http://www.cnblogs.com/networkcomms/p/4304362.html
在CS程序中，断线重连应该是一个常见的功能。
此处的断线重连主要指的是服务器端因为某种故障，服务器端程序或者系统进行了重新启动，客户端能够自动探测到服务器端掉线，并尝试重新进行连接
本程序基于来自英国的开源c#通信框架的networkcomms（2.3.1版本）
先看一下效果
初始状态：
当服务器端程序关闭后，客户端会自动探测到，并在客户端显示相关信息
然后，我们设定为每隔5秒重连一次，可以自定义设置重连的次数，比如说重连50次，如果还没有重连成功，则放弃重连
然后我们重新启动服务器端,客户端会显示重连成功.
具体步骤如下：
需要修改几处NetworkComms2.3.1通信框架中的代码
第一步：修改ConnectionInfo类的NoteConnectionShutdown方法
该方法原来是：
internal void NoteConnectionShutdown()
{
lock (internalLocker)
ConnectionState = ConnectionState.Shutdown;
}
修改后为：
private bool reconnectFlag = false;
/// <summary>
/// 是否为重连接模式
/// </summary>
public bool ReconnectFlag
{
get { return reconnectFlag; }
set { reconnectFlag = value; }
}
/// <summary>
/// Note this connection as shutdown
/// </summary>
internal void NoteConnectionShutdown()
{
lock (internalLocker)
ConnectionState = ConnectionState.Shutdown;
//添加以下代码 初始状态为False 触发连接状态改变事件
if (reconnectFlag == false)
{
StateChanged.Raise(this, new StringEventArgs("连接出现异常"));
}
}
//添加状态改变事件
public event EventHandler<StringEventArgs> StateChanged;
第二步：在NetworkComms库类中添加相关的代码如下：
using System;
using System.Collections.Generic;
using System.Text;
using NetworkCommsDotNet.Tools;
namespace NetworkCommsDotNet
{
public static class Extensions
{
public static void Raise<T>(this EventHandler<T> handler, object sender, T args) where T : EventArgs
{
if (handler != null)
handler(sender, args);
}
}
public class StringEventArgs : EventArgs
{
public StringEventArgs(string text)
{
Text = text;
}
public string Text { get; set; }
}
}
namespace System.Runtime.CompilerServices
{
[AttributeUsage(AttributeTargets.Method | AttributeTargets.Class | AttributeTargets.Assembly)]
public sealed class ExtensionAttribute : Attribute { }
}
第三步：在NetworkComms静态类中添加如下方法：
public static void ClearDic()
{
lock (globalDictAndDelegateLocker)
{
allConnectionsById.Clear();
allConnectionsByEndPoint.Clear();
oldNetworkIdentifierToConnectionInfo.Clear();
}
}
如果您使用的是V3版本，代码稍微变化：
public static void ClearDic()
{
lock (globalDictAndDelegateLocker)
{
allConnectionsByIdentifier.Clear();
allConnectionsByEndPoint.Clear();
oldNetworkIdentifierToConnectionInfo.Clear();
}
}
客户端代码：
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using NetworkCommsDotNet;
using DPSBase;
using System.Net;
using System.Threading;
namespace AppClient
{
public partial class Form1 : Form
{
//连接信息类
public ConnectionInfo connnectionInfo = null;
//连接类
Connection connection;
public Form1()
{
InitializeComponent();
}
//在窗体上显示新信息
void Form_ConnectionStatusNotify(object sender, StringEventArgs e)
{
if (this.InvokeRequired)
{
this.Invoke(new EventHandler<StringEventArgs>(this.Form_ConnectionStatusNotify), sender, e);
}
else
{
lblLink.Text = e.Text;
lblLink.ForeColor = Color.Blue;
}
}
private bool ServerNotifyClose = false;
public event EventHandler<StringEventArgs> ConnectionStatusNotify;
void connnectionInfo_StateChanged(object sender, StringEventArgs e)
{
//如果不是服务器通知关闭，则自动重连，如果是服务器通知关闭，则不作处理
//本Demo中没有使用ServerNotifyClose
if (ServerNotifyClose == false)
{
//更新连接信息类 设置为重连模式
connnectionInfo.ReconnectFlag = true;
ConnectionStatusNotify.Raise(this, new StringEventArgs("可能由于服务器的故障，与服务器端的连接已断开"));
int num = 0;
int retryCount = 30;
int retrySpanInMSecs = 5000;
do
{
try
{
NetworkComms.ClearDic();
connection = TCPConnection.GetConnection(connnectionInfo);
ConnectionStatusNotify.Raise(this, new StringEventArgs("重连成功"));
connnectionInfo.ReconnectFlag = false;
break;
}
catch (Exception ex)
{
num++;
if (num < retryCount)
{
ConnectionStatusNotify.Raise(this, new StringEventArgs("正在进行第" + num + "次重连"));
Thread.Sleep(retrySpanInMSecs);
}
}
}
while (num < retryCount);
}
}
private void button1_Click(object sender, EventArgs e)
{
connnectionInfo = new ConnectionInfo(txtIP.Text, int.Parse(txtPort.Text));
//如果不成功，会弹出异常信息
connection = TCPConnection.GetConnection(connnectionInfo);
button1.Enabled = false;
button1.Text = "连接成功";
//订阅连接信息类中的连接状态改变事件
connnectionInfo.StateChanged += new EventHandler<StringEventArgs>(connnectionInfo_StateChanged);
this.ConnectionStatusNotify += new EventHandler<StringEventArgs>(Form_ConnectionStatusNotify);
}
//获取水果相关信息
private void button2_Click(object sender, EventArgs e)
{
if (listBox1.SelectedIndex > -1)
{
string resMsg = connection.SendReceiveObject<string>("ReqFruitEngName", "ResFruitEngName", 5000, listBox1.Text);
MessageBox.Show("您选择的水果的英文名称是：" + resMsg);
}
else
{
MessageBox.Show("请选择一项");
}
}
private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
this.Dispose();
}
}
}
服务器端无需额外的设置。