TextWriterTraceListener Constructor (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.

Namespace:   System.Diagnostics
Assembly:  System (in System.dll)

Public Sub New (
	fileName As String,
	name As String
)

Parameters

fileName
Type: System.String

The name of the file the TextWriterTraceListener writes to.

name
Type: System.String

The name of the new instance.

Exception Condition
ArgumentNullException

The stream is null.

This constructor initializes the Name property to the name parameter or to an empty string (""), if the name parameter is null.

The following code example creates a TextWriterTraceListener using the TextWriterTraceListener(String, String) constructor, then adds it to the TraceListenerCollection. The example writes two messages to this TextWriterTraceListener, then writes a message to all TraceListener objects in the TraceListenerCollection. Finally, it flushes and closes the TextWriterTraceListener.

Imports System
Imports System.Diagnostics
Imports Microsoft.VisualBasic

Module TWTLConStringNameMod

    Const LISTENER_NAME As String = "myStringListener"

    ' args(0) is the specification of the trace log file.
    Sub Main(ByVal args() As String)

        ' Verify that a parameter was entered.
        If args.Length = 0 Then
            Console.WriteLine("Enter a trace file specification.")

        Else
            ' Create a TextWriterTraceListener object that takes a 
            ' file specification.
            Dim textListener As TextWriterTraceListener
            Try
                textListener = _
                    New TextWriterTraceListener(args(0), LISTENER_NAME)
                Trace.Listeners.Add(textListener)
            Catch ex As Exception
                Console.WriteLine( _
                    "Error creating TextWriterTraceListener for trace " & _
                    "file ""{0}"":" & vbCrLf & "{1}", args(0), ex.Message)
                Return
            End Try

            ' Write these messages only to this TextWriterTraceListener.
            textListener.WriteLine( _
                "This is trace listener named """ & textListener.Name & """")
            textListener.WriteLine("Trace written to a file: " & _
                vbCrLf & "    """ & args(0) & """")

            ' Write a message to all trace listeners.
            Trace.WriteLine(String.Format( _
                "This trace message written {0} to all listeners.", Now))

            ' Flush and close the output.
            Trace.Flush()
            textListener.Flush()
            textListener.Close()
        End If
    End Sub
End Module

.NET Framework
Available since 1.1
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