BooleanSwitch Class

Definition

Namespace:

System.Diagnostics

Assembly:

System.Diagnostics.TraceSource.dll

Source:

BooleanSwitch.cs

Provides a simple on/off switch that controls debugging and tracing output.

public ref class BooleanSwitch : System::Diagnostics::Switch

public class BooleanSwitch : System.Diagnostics.Switch

type BooleanSwitch = class
    inherit Switch

Public Class BooleanSwitch
Inherits Switch

Inheritance

Object

Switch

BooleanSwitch

Examples

The following example creates a BooleanSwitch and uses the switch to determine whether to print an error message. You create the switch at the class level. The Main method passes its location to MyMethod, which prints an error message and where the error occurred.

public ref class BooleanSwitchTest
{
private:

   /* Create a BooleanSwitch for data.*/
   static BooleanSwitch^ dataSwitch = gcnew BooleanSwitch( "Data","DataAccess module" );

public:
   static void MyMethod( String^ location )
   {
      
      //Insert code here to handle processing.
      if ( dataSwitch->Enabled )
            Console::WriteLine( "Error happened at {0}", location );
   }

};

int main()
{
   
   //Run the method which writes an error message specifying the location of the error.
   BooleanSwitchTest::MyMethod( "in main" );
}

// Class level declaration.
/* Create a BooleanSwitch for data.*/
static BooleanSwitch dataSwitch = new BooleanSwitch("Data", "DataAccess module");

static public void MyMethod(string location)
{
    //Insert code here to handle processing.
    if (dataSwitch.Enabled)
        Console.WriteLine("Error happened at " + location);
}

public static void Main(string[] args)
{
    //Run the method which writes an error message specifying the location of the error.
    MyMethod("in Main");
}

' Class level declaration.
' Create a BooleanSwitch for data. 
Private Shared dataSwitch As New BooleanSwitch("Data", "DataAccess module")


Public Shared Sub MyMethod(location As String)
    ' Insert code here to handle processing.
    If dataSwitch.Enabled Then
        Console.WriteLine(("Error happened at " + location))
    End If
End Sub

' Entry point which delegates to C-style main function.
Public Overloads Shared Sub Main()
    Main(System.Environment.GetCommandLineArgs())
End Sub
 
Overloads Public Shared Sub Main(args() As String)
    ' Run the method which writes an error message specifying the location of the error.
    MyMethod("in Main")
End Sub

Remarks

You can use a Boolean trace switch to enable or disable messages based on their importance. Use the Enabled property to get the current value of the switch.

You can create a BooleanSwitch in your code and set the Enabled property directly to instrument a specific section of code.

For .NET Framework apps only, you can also enable or disable a BooleanSwitch through the application configuration file and then use the configured BooleanSwitch value in your application. To configure a BooleanSwitch, edit the configuration file that corresponds to the name of your application. Within this file, you can add or remove a switch, set a switch's value, or clear all the switches previously set by the application. The configuration file should be formatted like the following example.

<configuration>  
  <system.diagnostics>  
    <switches>  
      <add name="mySwitch" value="1"/>  
    </switches>  
  </system.diagnostics>  
</configuration>  

This example configuration section defines a BooleanSwitch with the DisplayName property set to mySwitch and the Enabled value set to true. Within your .NET Framework application, you can use the configured switch value by creating a BooleanSwitch with the same name, as shown in the following code example.

private:
    static BooleanSwitch^ boolSwitch = gcnew BooleanSwitch("mySwitch",
        "Switch in config file");

public:
    static void Main( )
    {
        //...
        Console::WriteLine("Boolean switch {0} configured as {1}",
            boolSwitch->DisplayName, ((Boolean^)boolSwitch->Enabled)->ToString());
        if (boolSwitch->Enabled)
        {
            //...
        }
    }

private static BooleanSwitch boolSwitch = new BooleanSwitch("mySwitch",
    "Switch in config file");

public static void Main()
{
    //...
    Console.WriteLine("Boolean switch {0} configured as {1}",
        boolSwitch.DisplayName, boolSwitch.Enabled.ToString());
    if (boolSwitch.Enabled)
    {
        //...
    }
}

Private Shared boolSwitch As new BooleanSwitch("mySwitch", _
    "Switch in config file")

Public Shared Sub Main( )
    '...
    Console.WriteLine("Boolean switch {0} configured as {1}",
        boolSwitch.DisplayName, boolSwitch.Enabled.ToString())
    If boolSwitch.Enabled = True Then
        '...
    End If
End Sub

For .NET Core and .NET 5+ apps, the Enabled property of the new switch is set to false by default.

For .NET Framework apps, the Enabled property is set using the value specified in the configuration file. Configure the switch with a value of 0 to set the Enabled property to false; configure the switch with a nonzero value to set the Enabled property to true. If the BooleanSwitch constructor cannot find initial switch settings in the configuration file, the Enabled property of the new switch is set to false.

You must enable tracing or debugging to use a switch. 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:DEBUG flag to the compiler command line when you compile your code, or you can add #define DEBUG to the top of your file. In Visual Basic, add the /d:DEBUG=True flag to the compiler command line.

• To enable tracing in C#, add the /d:TRACE flag to the compiler command line when you compile your code, or add #define TRACE to the top of your file. In Visual Basic, add the /d:TRACE=True flag to the compiler command line.

Note

These debug and trace compiler switches are not required when using the BooleanSwitch class in isolation. They are only required in conjunction with Trace or Debug methods that are conditionally compiled.

For more information on instrumenting your application, see Debug and Trace. For more information about configuring and using trace switches, see Trace Switches.

Note

To improve performance, you can make BooleanSwitch members static in your class.

Constructors

BooleanSwitch(String, String)	Initializes a new instance of the BooleanSwitch class with the specified display name and description.
BooleanSwitch(String, String, String)	Initializes a new instance of the BooleanSwitch class with the specified display name, description, and default switch value.

Properties

Attributes	Gets the custom switch attributes defined in the application configuration file. (Inherited from Switch)
DefaultValue	Gets the default value assigned in the constructor. (Inherited from Switch)
Description	Gets a description of the switch. (Inherited from Switch)
DisplayName	Gets a name used to identify the switch. (Inherited from Switch)
Enabled	Gets or sets a value indicating whether the switch is enabled or disabled.
SwitchSetting	Gets or sets the current setting for this switch. (Inherited from Switch)
Value	Gets or sets the value of the switch. (Inherited from Switch)

Methods

Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetSupportedAttributes()	Gets the custom attributes supported by the switch. (Inherited from Switch)
GetType()	Gets the Type of the current instance. (Inherited from Object)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
OnSwitchSettingChanged()	Invoked when the SwitchSetting property is changed. (Inherited from Switch)
OnValueChanged()	Determines whether the new value of the Value property can be parsed as a Boolean value.
Refresh()	Refreshes the trace configuration data. (Inherited from Switch)
ToString()	Returns a string that represents the current object. (Inherited from Object)

See also

• Switch
• TraceSwitch
• Debug
• Trace