文章目录
概要
SocketExceptions 有两种类型：致命异常和非致命异常。
在 Microsoft C# 程序或 Microsoft Visual Basic .NET 程序中，通常有 try 块、catch 块和 finally 块。当在 try 块中获得异常时，将在 catch 块中捕获该异常。如果是致命错误，在退出应用程序之前，可以在 finally 块中进行一些清理工作。
但是，有时会遇到与套接字相关的、非致命的异常，如 Connection Refused（连接被拒绝）和 Receive Timed-Out（接收超时）。您可以适度地处理这些异常，然后继续执行应用程序。
下面的客户端示例重试连接三次，并适度地处理 WSAECONNREFUSED (10061) 错误。Connect 语句有一个单独的 try-catch 块。Connect 语句引发的所有 Socket 异常都将在相应的 catch 块中捕获。
更多信息
using System;
using System.Net.Sockets;
using System.Net;
using System.Text;
class App
{
[STAThread]
static void Main(string[] args)
{
string msg = "Hello server";
Byte[] buffer = ASCIIEncoding.ASCII.GetBytes(msg);
Byte[] resBuffer = new Byte[500];
int retry = 1, bytes;
bool runApp = true;
try
{
Console.Write("Enter the Server you would like to connect: ");
String serverName = Console.ReadLine();
IPAddress ip = Dns.Resolve(serverName).AddressList[0];
Console.Write("Enter the Port: ");
int Port = Int32.Parse(Console.ReadLine());
IPEndPoint serverEP = new IPEndPoint(ip,Port);
Socket clientSock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
while (retry <= 3)
{
try
{
clientSock.Connect(serverEP);
}
catch (SocketException e)
{
if (e.ErrorCode == 10061)
{
Console.WriteLine("Connect error. Trying to connect again......");
retry++;
runApp = false;
}
else
{
runApp = true;
break;
}
}
}
if (runApp)
{
clientSock.Send(buffer,buffer.Length,0);
bytes = clientSock.Receive(resBuffer);
Console.WriteLine("Received Data from Server : " + ASCIIEncoding.ASCII.GetString(resBuffer));
clientSock.Shutdown(SocketShutdown.Both);
}
clientSock.Close();
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
}
}
这篇文章中的信息适用于:
- Microsoft Visual Studio .NET (2002), Professional Edition
| 最近更新: | 2003-8-6 (1.0) |
| 关键字 | kbhowto KB321237 |