EventInstance Constructors

Definition

Namespace:

System.Diagnostics

Assembly:

System.Diagnostics.EventLog.dll

Initializes a new instance of the EventInstance class using language-neutral information to define an event log entry.

Overloads

EventInstance(Int64, Int32)	Initializes a new instance of the EventInstance class using the specified resource identifiers for the localized message and category text of the event entry.
EventInstance(Int64, Int32, EventLogEntryType)	Initializes a new instance of the EventInstance class using the specified resource identifiers for the localized message and category text of the event entry and the specified event log entry type.

EventInstance(Int64, Int32)

Source:

EventData.cs

Initializes a new instance of the EventInstance class using the specified resource identifiers for the localized message and category text of the event entry.

public:
 EventInstance(long instanceId, int categoryId);

public EventInstance (long instanceId, int categoryId);

new System.Diagnostics.EventInstance : int64 * int -> System.Diagnostics.EventInstance

Public Sub New (instanceId As Long, categoryId As Integer)

Parameters

instanceId

Int64

A resource identifier that corresponds to a string defined in the message resource file of the event source.

categoryId

Int32

A resource identifier that corresponds to a string defined in the category resource file of the event source, or zero to specify no category for the event.

Exceptions

ArgumentOutOfRangeException

The instanceId parameter is a negative value or a value larger than UInt32.MaxValue.

-or-

The categoryId parameter is a negative value or a value larger than UInt16.MaxValue.

Examples

The following code example writes an informational event entry, and then reuses the EventInstance to write an entry for a warning event to an existing event log. The event message text is specified using a resource identifier in a message resource file. The code example assumes that the corresponding message resource file has been registered for the source.

// Ensure that the source has already been registered using
// EventLogInstaller or EventLog.CreateEventSource.
String^ sourceName = "SampleApplicationSource";
if ( EventLog::SourceExists( sourceName ) )
{
   // Define an informational event with no category.
   // The message identifier corresponds to the message text in the
   // message resource file defined for the source.
   EventInstance ^ myEvent = gcnew EventInstance( UpdateCycleCompleteMsgId,0 );

   // Write the event to the event log using the registered source.
   EventLog::WriteEvent( sourceName, myEvent, 0 );

   // Reuse the event data instance for another event entry.
   // Set the entry category and message identifiers for
   // the appropriate resource identifiers in the resource files
   // for the registered source.  Set the event type to Warning.
   myEvent->CategoryId = RefreshCategoryMsgId;
   myEvent->EntryType = EventLogEntryType::Warning;
   myEvent->InstanceId = ServerConnectionDownMsgId;

   // Write the event to the event log using the registered source.
   // Insert the machine name into the event message text.
   array<String^>^ss = {Environment::MachineName};
   EventLog::WriteEvent( sourceName, myEvent, ss );
}
else
{
   Console::WriteLine( "Warning - event source {0} not registered", sourceName );
}

// Ensure that the source has already been registered using
// EventLogInstaller or EventLog.CreateEventSource.

string sourceName = "SampleApplicationSource";
if(EventLog.SourceExists(sourceName))
{
    // Define an informational event with no category.
    // The message identifier corresponds to the message text in the
    // message resource file defined for the source.
    EventInstance myEvent = new EventInstance(UpdateCycleCompleteMsgId, 0);

    // Write the event to the event log using the registered source.
    EventLog.WriteEvent(sourceName, myEvent);

    // Reuse the event data instance for another event entry.
    // Set the entry category and message identifiers for
    // the appropriate resource identifiers in the resource files
    // for the registered source.  Set the event type to Warning.

    myEvent.CategoryId = RefreshCategoryMsgId;
    myEvent.EntryType = EventLogEntryType.Warning;
    myEvent.InstanceId = ServerConnectionDownMsgId;

    // Write the event to the event log using the registered source.
    // Insert the machine name into the event message text.
    EventLog.WriteEvent(sourceName, myEvent, Environment.MachineName);
}
else
{
    Console.WriteLine("Warning - event source {0} not registered",
        sourceName);
}

' Ensure that the source has already been registered using
' EventLogInstaller or EventLog.CreateEventSource.
Dim sourceName as String = "SampleApplicationSource"
If EventLog.SourceExists(sourceName)
    
    ' Define an informational event with no category.
    ' The message identifier corresponds to the message text in the
    ' message resource file defined for the source.
    Dim myEvent As EventInstance = New EventInstance(UpdateCycleCompleteMsgId, 0)
    ' Write the event to the event log using the registered source.
    EventLog.WriteEvent(sourceName, myEvent)

    ' Reuse the event data instance for another event entry.
    ' Set the entry category and message identifiers for
    ' the appropriate resource identifiers in the resource files
    ' for the registered source.  Set the event type to Warning.

    myEvent.CategoryId = RefreshCategoryMsgId
    myEvent.EntryType = EventLogEntryType.Warning
    myEvent.InstanceId = ServerConnectionDownMsgId

    ' Write the event to the event log using the registered source.
    ' Insert the machine name into the event message text.
    EventLog.WriteEvent(sourceName, myEvent, Environment.MachineName)

Else 
    Console.WriteLine("Warning - event source {0} not registered", _
        sourceName)
End If

The code example uses the following message text file, built into the resource library EventLogMsgs.dll. A message text file is the source from which the message resource file is created. The message text file defines the resource identifiers and text for the category, event message, and parameter insertion strings.

; // EventLogMsgs.mc  
; // ********************************************************  

; // Use the following commands to build this file:  

; //   mc -s EventLogMsgs.mc  
; //   rc EventLogMsgs.rc  
; //   link /DLL /SUBSYSTEM:WINDOWS /NOENTRY /MACHINE:x86 EventLogMsgs.Res   
; // ********************************************************  

; // - Event categories -  
; // Categories must be numbered consecutively starting at 1.  
; // ********************************************************  

MessageId=0x1  
Severity=Success  
SymbolicName=INSTALL_CATEGORY  
Language=English  
Installation  
.  

MessageId=0x2  
Severity=Success  
SymbolicName=QUERY_CATEGORY  
Language=English  
Database Query  
.  

MessageId=0x3  
Severity=Success  
SymbolicName=REFRESH_CATEGORY  
Language=English  
Data Refresh  
.  

; // - Event messages -  
; // *********************************  

MessageId = 1000  
Severity = Success  
Facility = Application  
SymbolicName = AUDIT_SUCCESS_MESSAGE_ID_1000  
Language=English  
My application message text, in English, for message id 1000, called from %1.  
.  

MessageId = 1001  
Severity = Warning  
Facility = Application  
SymbolicName = AUDIT_FAILED_MESSAGE_ID_1001  
Language=English  
My application message text, in English, for message id 1001, called from %1.  
.  

MessageId = 1002  
Severity = Success  
Facility = Application  
SymbolicName = GENERIC_INFO_MESSAGE_ID_1002  
Language=English  
My generic information message in English, for message id 1002.  
.  

MessageId = 1003  
Severity = Warning  
Facility = Application  
SymbolicName = GENERIC_WARNING_MESSAGE_ID_1003  
Language=English  
My generic warning message in English, for message id 1003, called from %1.  
.  

MessageId = 1004  
Severity = Success  
Facility = Application  
SymbolicName = UPDATE_CYCLE_COMPLETE_MESSAGE_ID_1004  
Language=English  
The update cycle is complete for %%5002.  
.  

MessageId = 1005  
Severity = Warning  
Facility = Application  
SymbolicName = SERVER_CONNECTION_DOWN_MESSAGE_ID_1005  
Language=English  
The refresh operation did not complete because the connection to server %1 could not be established.  
.  

; // - Event log display name -  
; // ********************************************************  

MessageId = 5001  
Severity = Success  
Facility = Application  
SymbolicName = EVENT_LOG_DISPLAY_NAME_MSGID  
Language=English  
Sample Event Log  
.  

; // - Event message parameters -  
; //   Language independent insertion strings  
; // ********************************************************  

MessageId = 5002  
Severity = Success  
Facility = Application  
SymbolicName = EVENT_LOG_SERVICE_NAME_MSGID  
Language=English  
SVC_UPDATE.EXE  
.  

Remarks

To write an informational entry to an event log, initialize an EventInstance and pass it to the WriteEvent method. Set the instanceId to the resource identifier of the event message in the corresponding MessageResourceFile property for the source. Set the categoryId to a numeric category value, or the resource identifier of the event category in the CategoryResourceFile property for the source; set the categoryId to zero for no event category. The EntryType property for the new instance is set to Information by default.

The Event Viewer uses the resource identifiers to display the corresponding strings from the localized resource files for the source. You must register the source with the corresponding resource files before you can write events using resource identifiers.

See also

• CategoryId
• InstanceId
• WriteEvent
• EventSourceCreationData

EventInstance(Int64, Int32, EventLogEntryType)

Source:

EventData.cs

Initializes a new instance of the EventInstance class using the specified resource identifiers for the localized message and category text of the event entry and the specified event log entry type.

public:
 EventInstance(long instanceId, int categoryId, System::Diagnostics::EventLogEntryType entryType);

public EventInstance (long instanceId, int categoryId, System.Diagnostics.EventLogEntryType entryType);

new System.Diagnostics.EventInstance : int64 * int * System.Diagnostics.EventLogEntryType -> System.Diagnostics.EventInstance

Public Sub New (instanceId As Long, categoryId As Integer, entryType As EventLogEntryType)

Parameters

instanceId

Int64

A resource identifier that corresponds to a string defined in the message resource file of the event source.

categoryId

Int32

A resource identifier that corresponds to a string defined in the category resource file of the event source, or zero to specify no category for the event.

entryType

EventLogEntryType

An EventLogEntryType value that indicates the event type.

Exceptions

InvalidEnumArgumentException

entryType is not a valid EventLogEntryType value.

ArgumentOutOfRangeException

instanceId is a negative value or a value larger than UInt32.MaxValue.

-or-

categoryId is a negative value or a value larger than UInt16.MaxValue.

Examples

The following code example writes two audit event entries to the event log myNewLog. The code example creates a new event source and a new event log if they do not exist on the local computer. The event message text is specified using a resource identifier in a resource file.

// Create the event source if it does not exist.
String^ sourceName = "SampleApplicationSource";
if (  !EventLog::SourceExists( sourceName ) )
{
   
   // Call a local method to register the event log source
   // for the event log "myNewLog."  Use the resource file
   // EventLogMsgs.dll in the current directory for message text.
   String^ messageFile = String::Format( "{0}\\{1}", System::Environment::CurrentDirectory, "EventLogMsgs.dll" );
   CreateEventSourceSample1( messageFile );
}

// Get the event log corresponding to the existing source.
String^ myLogName = EventLog::LogNameFromSourceName( sourceName, "." );
EventLog^ myEventLog = gcnew EventLog( myLogName,".",sourceName );

// Define two audit events.
// The message identifiers correspond to the message text in the
// message resource file defined for the source.
EventInstance ^ myAuditSuccessEvent = gcnew EventInstance( AuditSuccessMsgId,0,EventLogEntryType::SuccessAudit );
EventInstance ^ myAuditFailEvent = gcnew EventInstance( AuditFailedMsgId,0,EventLogEntryType::FailureAudit );

// Insert the method name into the event log message.
array<String^>^insertStrings = {"EventLogSamples.WriteEventSample1"};

// Write the events to the event log.
myEventLog->WriteEvent( myAuditSuccessEvent, insertStrings );

// Append binary data to the audit failure event entry.
array<Byte>^binaryData = {3,4,5,6};
myEventLog->WriteEvent( myAuditFailEvent, binaryData, insertStrings );

// Create the event source if it does not exist.
string sourceName = "SampleApplicationSource";
if(!EventLog.SourceExists(sourceName))
{
    // Call a local method to register the event log source
    // for the event log "myNewLog."  Use the resource file
    // EventLogMsgs.dll in the current directory for message text.

    string messageFile =  String.Format("{0}\\{1}",
        System.Environment.CurrentDirectory,
        "EventLogMsgs.dll");

    CreateEventSourceSample1(messageFile);
}

// Get the event log corresponding to the existing source.
string myLogName = EventLog.LogNameFromSourceName(sourceName,".");

EventLog myEventLog = new EventLog(myLogName, ".", sourceName);

// Define two audit events.

// The message identifiers correspond to the message text in the
// message resource file defined for the source.
EventInstance myAuditSuccessEvent = new EventInstance(AuditSuccessMsgId, 0, EventLogEntryType.SuccessAudit);
EventInstance myAuditFailEvent = new EventInstance(AuditFailedMsgId, 0, EventLogEntryType.FailureAudit);

// Insert the method name into the event log message.
string [] insertStrings = {"EventLogSamples.WriteEventSample1"};

// Write the events to the event log.

myEventLog.WriteEvent(myAuditSuccessEvent, insertStrings);

// Append binary data to the audit failure event entry.
byte [] binaryData = { 3, 4, 5, 6 };
myEventLog.WriteEvent(myAuditFailEvent, binaryData, insertStrings);

           Dim sourceName As String = "SampleApplicationSource"

           ' Create the event source if it does not exist.
           If Not EventLog.SourceExists(sourceName)
  
               ' Call a local method to register the event log source
               ' for the event log "myNewLog."  Use the resource file
               ' EventLogMsgs.dll in the current directory for message text.

               Dim messageFile As String =  String.Format("{0}\\{1}", _
                   System.Environment.CurrentDirectory, _
                   "EventLogMsgs.dll")

               CreateEventSourceSample1(messageFile)
           End If 

           ' Get the event log corresponding to the existing source.
           Dim myLogName As String = EventLog.LogNameFromSourceName(sourceName,".")
       
           Dim myEventLog As EventLog = new EventLog(myLogName, ".", sourceName)

           ' Define two audit events.
           Dim myAuditSuccessEvent As EventInstance = new EventInstance(AuditSuccessMsgId, 0, EventLogEntryType.SuccessAudit)
           Dim myAuditFailEvent As EventInstance = new EventInstance(AuditFailedMsgId, 0, EventLogEntryType.FailureAudit)

           ' Insert the method name into the event log message.
           Dim insertStrings() As String = {"EventLogSamples.WriteEventSample1"}
           
           ' Write the events to the event log.

           myEventLog.WriteEvent(myAuditSuccessEvent, insertStrings)

           ' Append binary data to the audit failure event entry.
           Dim binaryData() As Byte = { 7, 8, 9, 10 }
           myEventLog.WriteEvent(myAuditFailEvent, binaryData, insertStrings)

The code example uses the following message text file, built into the resource library EventLogMsgs.dll. A message text file is the source from which the message resource file is created. The message text file defines the resource identifiers and text for the category, event message, and parameter insertion strings.

; // EventLogMsgs.mc  
; // ********************************************************  

; // Use the following commands to build this file:  

; //   mc -s EventLogMsgs.mc  
; //   rc EventLogMsgs.rc  
; //   link /DLL /SUBSYSTEM:WINDOWS /NOENTRY /MACHINE:x86 EventLogMsgs.Res   
; // ********************************************************  

; // - Event categories -  
; // Categories must be numbered consecutively starting at 1.  
; // ********************************************************  

MessageId=0x1  
Severity=Success  
SymbolicName=INSTALL_CATEGORY  
Language=English  
Installation  
.  

MessageId=0x2  
Severity=Success  
SymbolicName=QUERY_CATEGORY  
Language=English  
Database Query  
.  

MessageId=0x3  
Severity=Success  
SymbolicName=REFRESH_CATEGORY  
Language=English  
Data Refresh  
.  

; // - Event messages -  
; // *********************************  

MessageId = 1000  
Severity = Success  
Facility = Application  
SymbolicName = AUDIT_SUCCESS_MESSAGE_ID_1000  
Language=English  
My application message text, in English, for message id 1000, called from %1.  
.  

MessageId = 1001  
Severity = Warning  
Facility = Application  
SymbolicName = AUDIT_FAILED_MESSAGE_ID_1001  
Language=English  
My application message text, in English, for message id 1001, called from %1.  
.  

MessageId = 1002  
Severity = Success  
Facility = Application  
SymbolicName = GENERIC_INFO_MESSAGE_ID_1002  
Language=English  
My generic information message in English, for message id 1002.  
.  

MessageId = 1003  
Severity = Warning  
Facility = Application  
SymbolicName = GENERIC_WARNING_MESSAGE_ID_1003  
Language=English  
My generic warning message in English, for message id 1003, called from %1.  
.  

MessageId = 1004  
Severity = Success  
Facility = Application  
SymbolicName = UPDATE_CYCLE_COMPLETE_MESSAGE_ID_1004  
Language=English  
The update cycle is complete for %%5002.  
.  

MessageId = 1005  
Severity = Warning  
Facility = Application  
SymbolicName = SERVER_CONNECTION_DOWN_MESSAGE_ID_1005  
Language=English  
The refresh operation did not complete because the connection to server %1 could not be established.  
.  

; // - Event log display name -  
; // ********************************************************  

MessageId = 5001  
Severity = Success  
Facility = Application  
SymbolicName = EVENT_LOG_DISPLAY_NAME_MSGID  
Language=English  
Sample Event Log  
.  

; // - Event message parameters -  
; //   Language independent insertion strings  
; // ********************************************************  

MessageId = 5002  
Severity = Success  
Facility = Application  
SymbolicName = EVENT_LOG_SERVICE_NAME_MSGID  
Language=English  
SVC_UPDATE.EXE  
.  

Remarks

To write an entry to an event log, initialize an EventInstance and pass it to the WriteEvent method. Set the instanceId to the resource identifier of the event message in the corresponding MessageResourceFile property for the source. Set the categoryId to a numeric category value, or the resource identifier of the event category in the CategoryResourceFile property for the source; set the categoryId to zero for no event category.

The Event Viewer uses the resource identifiers to display the corresponding strings from the localized resource files for the source. You must register the source with the corresponding resource files before you can write events using resource identifiers.

Set the entryType to one of the pre-defined entry types. The Event Viewer uses the event type to determine which icon to display in the list view of the event log.

See also

• CategoryId
• InstanceId
• EventLogEntry
• WriteEvent
• EventSourceCreationData