[ZZ]使用命名管道通过网络在进程之间进行通信
命名管道提供的功能比匿名管道多。 其功能包括通过网络进行全双工通信和多个服务器实例；基于消息的通信；以及客户端模拟，这使得连接进程可在远程服务器上使用其自己的权限集。
下面的示例演示如何使用 NamedPipeClientStream 类创建命名管道。在此示例中，服务器进程创建了四个线程。每个线程可以接受一个客户端连接。连接的客户端进程随后向服务器提供一个文件名。如果客户端具有足够的权限，服务器进程就会打开文件并将其内容发送回客户端。
using
System;
using
System.IO;
using
System.IO.Pipes;
using
System.Threading;
class
PipeServer
{
static
int
numThreads
=
4
;
static
void
Main()
{
for
(
int
i
=
0
; i
<
numThreads; i
++
)
{
Thread newThread
=
new
Thread(ServerThread);
newThread.Start();
}
Console.WriteLine(
"
Press enter to exit.
"
);
Console.ReadLine();
}
//
Main()
private
static
void
ServerThread(
object
data)
{
NamedPipeServerStream pipeServer
=
new
NamedPipeServerStream(
"
testpipe
"
, PipeDirection.InOut, numThreads);
Console.WriteLine(
"
NamedPipeServerStream thread created.
"
);
//
Wait for a client to connect
pipeServer.WaitForConnection();
Console.WriteLine(
"
Client connected.
"
);
try
{
//
Read the request from the client. Once the client has
//
written to the pipe its security token will be available.
StreamReader sr
=
new
StreamReader(pipeServer);
StreamWriter sw
=
new
StreamWriter(pipeServer);
sw.AutoFlush
=
true
;
//
Verify our identity to the connected client using a
//
string that the client anticipates.
sw.WriteLine(
"
I am the one true server!
"
);
//
Obtain the filename from the connected client.
string
filename
=
sr.ReadLine();
//
Read in the contents of the file while impersonating the client.
ReadFileToStream fileReader
=
new
ReadFileToStream(pipeServer, filename);
//
Display the name of the user we are impersonating.
Console.WriteLine(
"
Reading file: {0} as user {1}.
"
,
pipeServer.GetImpersonationUserName(), filename);
pipeServer.RunAsClient(fileReader.Start);
pipeServer.Disconnect();
}
//
Catch the IOException that is raised if the pipe is broken
//
or disconnected.
catch
(IOException e)
{
Console.WriteLine(
"
ERROR: {0}
"
, e.Message);
}
pipeServer.Close();
}
//
ServerThread()
}
//
PipeServer
class
ReadFileToStream
{
private
string
m_filename;
private
Stream m_stream;
public
ReadFileToStream(Stream stream,
string
filename)
{
m_filename
=
filename;
m_stream
=
stream;
}
//
ReadFileToStream(stream, filename)
public
void
Start()
{
StreamWriter sw
=
new
StreamWriter(m_stream);
string
contents
=
File.ReadAllText(m_filename);
sw.WriteLine(contents);
sw.Flush();
}
//
Start()
}
//
ReadFileToStream
下面的示例演示使用 NamedPipeClientStream 类的客户端进程。客户端连接服务器进程并向服务器发送一个文件名。服务器随后将文件内容发送回客户端。文件内容随后显示在控制台上。
using
System;
using
System.IO;
using
System.IO.Pipes;
using
System.Security.Principal;
class
PipeClient
{
//
static int numThreads = 4;
static
void
Main()
{
NamedPipeClientStream pipeClient
=
new
NamedPipeClientStream(
"
localhost
"
,
"
testpipe
"
,
PipeDirection.InOut, PipeOptions.None,
TokenImpersonationLevel.Impersonation);
StreamWriter sw
=
new
StreamWriter(pipeClient);
StreamReader sr
=
new
StreamReader(pipeClient);
pipeClient.Connect();
sw.AutoFlush
=
true
;
//
Verify that this is the "true server"
if
(sr.ReadLine()
==
"
I am the one true server!
"
)
{
//
The client security token is sent with the first write.
sw.WriteLine(
"
c:\\textfile.txt
"
);
//
Print the file to the screen.
char
[] buffer
=
new
char
[
32
];
int
n;
do
{
n
=
sr.Read(buffer,
0
, buffer.Length);
Console.Write(buffer,
0
, n);
}
while
(n
>
0
);
}
else
{
Console.WriteLine(
"
Server could not be verified.
"
);
}
pipeClient.Close();
}
//
Main()
}
可靠编程
此示例中的客户端进程和服务器进程预期在同一台计算机上运行，因此提供给 NamedPipeClientStream 对象的服务器名称是 "localhost"。如果客户端进程和服务器进程位于不同的计算机上，则应该用运行服务器进程的计算机的网络名称来替换 "localhost"。
转自:http://msdn.microsoft.com/zh-cn/library/bb546085.aspx