TextWriterTraceListener
Class
Definition
Directs tracing or debugging output to a TextWriter or to a Stream, such as FileStream.
public class TextWriterTraceListener : System.Diagnostics.TraceListener
- Inheritance
- Derived
Inherited Members
System.Diagnostics.TraceListener
System.MarshalByRefObject
System.Object
Examples
The following example implements an instance of the TextWriterTraceListener class that uses a StreamWriter called myOutputWriter to write to a file named TestFile.txt. First the example creates a file for output. Then it creates the StreamWriter for the first text writer, assigns it the output file, and adds it to the Listeners. Then, the code outputs one line of text to the file. Finally, the example flushes the output buffer.
After running this sample, you can open the TestFile.txt file to see the output.
void main()
{
#if defined(TRACE)
// Create a file for output named TestFile.txt.
Stream^ myFile = File::Create( "TestFile.txt" );
// Create a new text writer using the output stream and
// add it to the trace listeners.
TextWriterTraceListener^ myTextListener =
gcnew TextWriterTraceListener( myFile );
Trace::Listeners->Add( myTextListener );
// Write output to the file.
Trace::Write( "Test output " );
// Flush the output.
Trace::Flush();
Trace::Close();
#endif
}
public class Sample
{
public static int Main(string[] args) {
// Create a file for output named TestFile.txt.
Stream myFile = File.Create("TestFile.txt");
/* Create a new text writer using the output stream, and add it to
* the trace listeners. */
TextWriterTraceListener myTextListener = new
TextWriterTraceListener(myFile);
Trace.Listeners.Add(myTextListener);
// Write output to the file.
Trace.Write("Test output ");
// Flush the output.
Trace.Flush();
return 0;
}
}
Public Class Sample
Public Shared Sub Main()
' Create a file for output named TestFile.txt.
Dim myFile As Stream = File.Create("TestFile.txt")
' Create a new text writer using the output stream, and add it to
' the trace listeners.
Dim myTextListener As New TextWriterTraceListener(myFile)
Trace.Listeners.Add(myTextListener)
' Write output to the file.
Trace.Write("Test output ")
' Flush the output.
Trace.Flush()
System.Environment.ExitCode = 0
End Sub
End Class
Remarks
The TextWriterTraceListener class provides the Writer property to get or set the text writer that receives the tracing or debugging output.
Important
This type implements the IDisposable interface. When you have finished using the type, you should dispose of it either directly or indirectly. To dispose of the type directly, call its Dispose method in a try/catch block. To dispose of it indirectly, use a language construct such as using (in C#) or Using (in Visual Basic). For more information, see the "Using an Object that Implements IDisposable" section in the IDisposable interface topic.
This class also provides methods to Close the Writer so that it no longer receives tracing or debugging output, to Flush the output buffer for the Writer, and to Write a message to the Writer.
You must enable tracing or debugging to use a trace listener. The following syntax is compiler specific. If you use compilers other than C# or Visual Basic, refer to the documentation for your compiler.
To enable debugging in C#, add the
/d:DEBUGflag to the compiler command line when you compile your code, or you can add#define DEBUGto the top of your file. In Visual Basic, add the/d:DEBUG=Trueflag to the compiler command line.To enable tracing in C#, add the
/d:TRACEflag to the compiler command line when you compile your code, or add#define TRACEto the top of your file. In Visual Basic, add the/d:TRACE=Trueflag to the compiler command line.
To add a trace listener, edit the configuration file that corresponds to the name of your application. Within this file, you can add a listener, set its type and set its parameter, remove a listener, or clear all the listeners previously set by the application. The configuration file should be formatted like the following example.
<configuration>
<system.diagnostics>
<trace autoflush="false" indentsize="4">
<listeners>
<add name="myListener"
type="System.Diagnostics.TextWriterTraceListener"
initializeData="TextWriterOutput.log" />
<remove name="Default" />
</listeners>
</trace>
</system.diagnostics>
</configuration>
Note
If an attempt is made to write to a file that is in use or unavailable, the file name is automatically prefixed by a GUID.
Constructors
| TextWriterTraceListener() |
Initializes a new instance of the TextWriterTraceListener class with TextWriter as the output recipient. |
| TextWriterTraceListener(Stream) |
Initializes a new instance of the TextWriterTraceListener class, using the stream as the recipient of the debugging and tracing output. |
| TextWriterTraceListener(TextWriter) |
Initializes a new instance of the TextWriterTraceListener class using the specified writer as recipient of the tracing or debugging output. |
| TextWriterTraceListener(String) |
Initializes a new instance of the TextWriterTraceListener class, using the file as the recipient of the debugging and tracing output. |
| TextWriterTraceListener(Stream, String) |
Initializes a new instance of the TextWriterTraceListener class with the specified name, using the stream as the recipient of the debugging and tracing output. |
| TextWriterTraceListener(TextWriter, String) |
Initializes a new instance of the TextWriterTraceListener class with the specified name, using the specified writer as recipient of the tracing or debugging output. |
| TextWriterTraceListener(String, String) |
Initializes a new instance of the TextWriterTraceListener class with the specified name, using the file as the recipient of the debugging and tracing output. |
Properties
| Writer |
Gets or sets the text writer that receives the tracing or debugging output. |
Methods
| Close() |
Closes the Writer so that it no longer receives tracing or debugging output. |
| Dispose(Boolean) |
Disposes this TextWriterTraceListener object. |
| Flush() |
Flushes the output buffer for the Writer. |
| Write(String) |
Writes a message to this instance's Writer. |
| WriteLine(String) |
Writes a message to this instance's Writer followed by a line terminator. The default line terminator is a carriage return followed by a line feed (\r\n). |