EventLog.Exists Method (String)


Determines whether the log exists on the local computer.

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

public 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 '"+myLog+"' exists.");
   Console.WriteLine("Log '"+myLog+"' does not exist.");


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

.NET Framework
Available since 1.1
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