Trace::WriteLine Method (Object^, String^)


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Writes a category name and the value of the object's ToString method to the trace listeners in the Listeners collection.

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

static void WriteLine(
	Object^ value,
	String^ category


Type: System::Object^

An Object whose name is sent to the Listeners.

Type: System::String^

A category name used to organize the output.

By default, the output is written to an instance of DefaultTraceListener.

The category parameter can be used to group output messages.

This method calls the WriteLine method of the trace listener.

The following example creates a TraceSwitch named generalSwitch. This switch is set outside the code sample.

If the switch is set to the TraceLevelError or higher, the example outputs the first error message to the Listeners. For information on adding a listener to the Listeners collection, see the TraceListenerCollection class.

Then, if the TraceLevel is set to Verbose, the example outputs the second error message on the same line as the first message. The second message is followed by a line terminator.

// Class-level declaration.
// Create a TraceSwitch.
   static TraceSwitch^ generalSwitch = 
      gcnew TraceSwitch( "General", "Entire Application" );

   static void MyErrorMethod( Object^ myObject, String^ category )
      #if defined(TRACE)
      // Write the message if the TraceSwitch level 
      // is set to Error or higher.
      if ( generalSwitch->TraceError )
         Trace::Write( "Invalid object for category. " );

      // Write a second message if the TraceSwitch level
      // is set to Verbose.
      if ( generalSwitch->TraceVerbose )
         Trace::WriteLine( myObject, category );

.NET Framework
Available since 1.1
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