如何在.NET中将单个TextWriter拆分为多个输出
本文关键字：拆分 输出 TextWriter 单个 NET | 更新日期: 2023-09-27 18:20:06
我从我的C#代码中调用了一个API，它有一个带有以下头的方法
public void ExternalFactory.SetOut(TextWriter outputStream)
我通常把这种方法称为
ExternalFactory.SetOut(Console.Out)
让API将其所有信息写入控制台。但是，除了写入控制台之外，我还想将这些信息存储在一个更永久的地方，例如文本文件。
我的第一个猜测是，我需要创建某种客户TextWriter来分割流，并将一个发送到控制台，另一个发送给StreamWriter。这里的正确方法是什么？
除了编译和首次使用之外，没有进行过测试，但可能会节省一些打字时间。令人烦恼的是，它还不存在。
/// <summary>
/// Spreads data out to multiple text writers.
/// </summary>
class TextWriterMulti : System.IO.TextWriter
{
private System.Collections.Generic.List<System.IO.TextWriter> writers = new System.Collections.Generic.List<System.IO.TextWriter>();
private System.IFormatProvider formatProvider = null;
private System.Text.Encoding encoding = null;
#region TextWriter Properties
public override System.IFormatProvider FormatProvider
{
get
{
System.IFormatProvider formatProvider = this.formatProvider;
if (formatProvider == null)
{
formatProvider = base.FormatProvider;
}
return formatProvider;
}
}
public override string NewLine
{
get { return base.NewLine; }
set
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.NewLine = value;
}
base.NewLine = value;
}
}
public override System.Text.Encoding Encoding
{
get
{
System.Text.Encoding encoding = this.encoding;
if (encoding == null)
{
encoding = System.Text.Encoding.Default;
}
return encoding;
}
}
#region TextWriter Property Setters
TextWriterMulti SetFormatProvider(System.IFormatProvider value)
{
this.formatProvider = value;
return this;
}
TextWriterMulti SetEncoding(System.Text.Encoding value)
{
this.encoding = value;
return this;
}
#endregion // TextWriter Property Setters
#endregion // TextWriter Properties
#region Construction/Destruction
public TextWriterMulti(System.Collections.Generic.IEnumerable<System.IO.TextWriter> writers)
{
this.Clear();
this.AddWriters(writers);
}
#endregion // Construction/Destruction
#region Public interface
public TextWriterMulti Clear()
{
this.writers.Clear();
return this;
}
public TextWriterMulti AddWriter(System.IO.TextWriter writer)
{
this.writers.Add(writer);
return this;
}
public TextWriterMulti AddWriters(System.Collections.Generic.IEnumerable<System.IO.TextWriter> writers)
{
this.writers.AddRange(writers);
return this;
}
#endregion // Public interface
#region TextWriter methods
public override void Close()
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Close();
}
base.Close();
}
protected override void Dispose(bool disposing)
{
foreach (System.IO.TextWriter writer in this.writers)
{
if (disposing)
{
writer.Dispose();
}
}
base.Dispose(disposing);
}
public override void Flush()
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Flush();
}
base.Flush();
}
//foreach (System.IO.TextWriter writer in this.writers)
//{
// writer;
//}
public override void Write(bool value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(value);
}
}
public override void Write(char value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(value);
}
}
public override void Write(char[] buffer)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(buffer);
}
}
public override void Write(decimal value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(value);
}
}
public override void Write(double value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(value);
}
}
public override void Write(float value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(value);
}
}
public override void Write(int value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(value);
}
}
public override void Write(long value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(value);
}
}
public override void Write(object value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(value);
}
}
public override void Write(string value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(value);
}
}
public override void Write(uint value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(value);
}
}
public override void Write(ulong value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(value);
}
}
public override void Write(string format, object arg0)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(format, arg0);
}
}
public override void Write(string format, params object[] arg)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(format, arg);
}
}
public override void Write(char[] buffer, int index, int count)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(buffer, index, count);
}
}
public override void Write(string format, object arg0, object arg1)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(format, arg0, arg1);
}
}
public override void Write(string format, object arg0, object arg1, object arg2)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.Write(format, arg0, arg1, arg2);
}
}
public override void WriteLine()
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine();
}
}
public override void WriteLine(bool value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(value);
}
}
public override void WriteLine(char value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(value);
}
}
public override void WriteLine(char[] buffer)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(buffer);
}
}
public override void WriteLine(decimal value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(value);
}
}
public override void WriteLine(double value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(value);
}
}
public override void WriteLine(float value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(value);
}
}
public override void WriteLine(int value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(value);
}
}
public override void WriteLine(long value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(value);
}
}
public override void WriteLine(object value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(value);
}
}
public override void WriteLine(string value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(value);
}
}
public override void WriteLine(uint value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(value);
}
}
public override void WriteLine(ulong value)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(value);
}
}
public override void WriteLine(string format, object arg0)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(format, arg0);
}
}
public override void WriteLine(string format, params object[] arg)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(format, arg);
}
}
public override void WriteLine(char[] buffer, int index, int count)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(buffer, index, count);
}
}
public override void WriteLine(string format, object arg0, object arg1)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(format, arg0, arg1);
}
}
public override void WriteLine(string format, object arg0, object arg1, object arg2)
{
foreach (System.IO.TextWriter writer in this.writers)
{
writer.WriteLine(format, arg0, arg1, arg2);
}
}
#endregion // TextWriter methods
}
我使用log4net而不是标准的I/O设施来做这类事情。我将log4net配置为同时登录到控制台和日志文件，使用ConsoleAppender和FileAppnder或RollingFileAppender。
好的方面是，您可以设置日志消息模板来捕获除了日志消息之外的各种有用信息（一天中的时间、线程/进程id、机器名称等）。
您还可以登录到SQL Server、事件日志或远程处理接收器。
轻松！
下面是一个示例TextWriter实现，它通过log4net:路由所有内容
using System;
using System.IO;
using System.Text;
using log4net ;
namespace ConsoleApplication22
{
public class Log4NetTextWriter : TextWriter, IDisposable
{
private static ILog log = log4net.LogManager.GetLogger( typeof(Log4NetTextWriter) ) ;
#region properties
private StringBuilder buffer { get ; set ; }
public override Encoding Encoding
{
get
{
// since this TextWrite is writing to log4net, we have no idea what the final encoding might be.
// It all depends on the log4net configuration: tthe appender or appenders that wind up handling the logged message
// determine the final encoding.
//
// Might make more sense to return Encoding.UTF8 though, just to return something.
throw new NotImplementedException() ;
}
}
#endregion properties ;
public override void Flush()
{
if ( this.buffer != null && this.buffer.Length > 0 )
{
this.WriteLine() ;
}
return ;
}
public override void Close()
{
base.Close();
}
protected override void Dispose( bool disposing )
{
this.Flush() ;
base.Dispose( disposing );
}
#region public constructors
public Log4NetTextWriter() : this( null )
{
return ;
}
public Log4NetTextWriter( IFormatProvider formatProvider ) : base( formatProvider )
{
this.buffer = new StringBuilder() ;
}
#endregion public constructors
#region public Write() overloads
public override void Write( bool value )
{
this.buffer.Append( value ) ;
return ;
}
public override void Write( char value )
{
this.buffer.Append( value ) ;
return ;
}
public override void Write( char[] buffer )
{
this.buffer.Append( buffer ) ;
return ;
}
public override void Write( char[] buffer , int index , int count )
{
this.buffer.Append( buffer , index , count ) ;
return ;
}
public override void Write( decimal value )
{
this.buffer.Append( value ) ;
return ;
}
public override void Write( double value )
{
this.buffer.Append( value ) ;
return ;
}
public override void Write( float value )
{
this.buffer.Append( value ) ;
return ;
}
public override void Write( int value )
{
this.buffer.Append( value ) ;
return ;
}
public override void Write( long value )
{
this.buffer.Append( value ) ;
return ;
}
public override void Write(object value)
{
this.buffer.Append( value ) ;
return ;
}
public override void Write( string format , object arg0 )
{
this.buffer.AppendFormat( this.FormatProvider , format , arg0 ) ;
return ;
}
public override void Write( string format , object arg0 , object arg1 )
{
this.buffer.AppendFormat( this.FormatProvider , format , arg0 , arg1 ) ;
return ;
}
public override void Write( string format , object arg0 , object arg1 , object arg2 )
{
this.buffer.AppendFormat( this.FormatProvider , format , arg0 , arg1 , arg2 );
return ;
}
public override void Write( string format , params object[] arg )
{
this.buffer.AppendFormat( this.FormatProvider , format , arg ) ;
return ;
}
public override void Write( string value )
{
this.buffer.Append( value );
return ;
}
public override void Write( uint value )
{
this.buffer.Append( value );
return ;
}
public override void Write( ulong value )
{
this.buffer.Append( value );
return ;
}
public override void WriteLine()
{
string logMessage = this.buffer.ToString() ;
this.buffer.Length = 0 ;
log.Info( logMessage ) ;
return ;
}
#endregion public Write() overloads
#region public WriteLine() overloads
public override void WriteLine( bool value )
{
this.Write( value ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( char value )
{
this.Write( value ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( char[] buffer )
{
this.Write( buffer ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( char[] buffer , int index , int count )
{
this.Write( buffer , index , count ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( decimal value )
{
this.Write( value ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( double value )
{
this.Write( value ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( float value )
{
this.Write( value ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( int value )
{
this.Write( value ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( long value )
{
this.Write( value ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( object value )
{
this.Write( value ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( string format , object arg0 )
{
this.Write( format , arg0 ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( string format , object arg0 , object arg1 )
{
this.Write( format , arg0 , arg1 ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( string format , object arg0 , object arg1 , object arg2 )
{
this.Write( format , arg0 , arg1 , arg2 ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( string format , params object[] arg )
{
this.Write( format , arg ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( string value )
{
this.Write( value ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( uint value )
{
this.Write( value ) ;
this.WriteLine() ;
return ;
}
public override void WriteLine( ulong value )
{
this.Write( value ) ;
this.WriteLine() ;
return ;
}
#endregion public WriteLine() overloads
}
}
下面是一个示例log4net配置文件。这一个同时登录到控制台和日志文件，并根据大小自动滚动（也可以根据日期/时间或每次执行滚动）。
<log4net>
<!-- Log to the console -->
<appender name="Console" type="log4net.Appender.ConsoleAppender">
<layout type="log4net.Layout.PatternLayout">
<!-- Pattern to output the caller's file name and line number -->
<conversionPattern value="%5level [%thread] (%file:%line) - %message%newline" />
</layout>
</appender>
<!-- Log to a log file. This particular setup should log to a static file name 'log.txt' -->
<!-- When it hits 100KB in size, it rolls, keeping up to 10 archived files. The archived -->
<!-- files are named 'log.text.1', 'log.txt.2', ... , 'log.txt.10' -->
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="log.txt" />
<appendToFile value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="100KB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>
<root>
<level value="DEBUG" />
<appender-ref ref="Console" />
<appender-ref ref="RollingFile" />
</root>
</log4net>
要配置log4net，最简单的方法是在AssemblyInfo.cs中放入XmlConfigurator属性，因此：
// Configure log4net using the .log4net file
[assembly: log4net.Config.XmlConfigurator(ConfigFileExtension="log4net",Watch=true)]
// This will cause log4net to look for a configuration file
// called TestApp.exe.log4net in the application base
// directory (i.e. the directory containing TestApp.exe)
// The config file will be watched for changes.
当程序运行时，您可以打开或关闭日志记录，或者只需编辑和保存配置文件即可更改其配置。log4net监视配置文件的更改并动态重新配置自己。
您的第一个猜测是正确的。您可以对其进行泛化，并编写一个"分布式"文本编写器，它接受一个文本编写器列表作为构建时间参数，并将接收到的所有输入分配给每个文本编写器。
您只需向流（文本文件）和显示（控制台）发送一份数据副本。