EventLog::Exists Method (String^)


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Determines whether the log exists on the local computer.

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

static bool Exists(
	String^ logName


Type: System::String^

The name of the log to search for. Possible values include: Application, Security, System, other application-specific logs (such as those associated with Active Directory), or any custom log on the computer.

Return Value

Type: System::Boolean

true if the log exists on the local computer; otherwise, false.

Exception Condition

The logName is null or the value is empty.

Use this method to determine if a log exists on the local computer. If you want to determine whether a source exists on the local computer, use SourceExists.

Because this method accesses the registry, you must have the appropriate registry permissions on the local computer; otherwise, the query returns false.

Because you cannot give a new log the name of an existing log on the same computer, use this method before creating a new log to determine if the specified logName already exists on the local computer. The logName parameter is not case sensitive.

Exists is a static method, so it can be called on the class itself. It is not necessary to create an instance of EventLog to call Exists.

      String^ myLog = "myNewLog";
      if ( EventLog::Exists( myLog ) )
         Console::WriteLine( "Log '{0}' exists.", myLog );
         Console::WriteLine( "Log '{0}' does not exist.", myLog );
   catch ( Exception^ e ) 
      Console::WriteLine( "Exception: {0}", e->Message );



for administering event log information on the computer. Associated enumeration: EventLogPermissionAccess::Administer

.NET Framework
Available since 1.1
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