EventSourceCreationData.CategoryCount Property
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Gets or sets the number of categories in the category resource file.
public:
property int CategoryCount { int get(); void set(int value); };public int CategoryCount { get; set; }member this.CategoryCount : int with get, setPublic Property CategoryCount As IntegerProperty Value
The number of categories in the category resource file. The default value is zero.
Exceptions
The property is set to a negative value or to a value larger than UInt16.MaxValue.
Examples
The following code example determines whether the event source named SampleApplicationSource is registered on the local computer. If the event source does not exist, the example sets the message resource file for the source and creates the new event source. Finally, the code example sets the localized display name for the event log, using the resource identifier value in DisplayNameMsgId and the resource file path in messageFile.
void CreateEventSourceSample1( String^ messageFile )
{
String^ myLogName;
String^ sourceName = "SampleApplicationSource";
// Create the event source if it does not exist.
if ( !EventLog::SourceExists( sourceName ) )
{
// Create a new event source for the custom event log
// named "myNewLog."
myLogName = "myNewLog";
EventSourceCreationData ^ mySourceData = gcnew EventSourceCreationData( sourceName,myLogName );
// Set the message resource file that the event source references.
// All event resource identifiers correspond to text in this file.
if ( !System::IO::File::Exists( messageFile ) )
{
Console::WriteLine( "Input message resource file does not exist - {0}", messageFile );
messageFile = "";
}
else
{
// Set the specified file as the resource
// file for message text, category text, and
// message parameter strings.
mySourceData->MessageResourceFile = messageFile;
mySourceData->CategoryResourceFile = messageFile;
mySourceData->CategoryCount = CategoryCount;
mySourceData->ParameterResourceFile = messageFile;
Console::WriteLine( "Event source message resource file set to {0}", messageFile );
}
Console::WriteLine( "Registering new source for event log." );
EventLog::CreateEventSource( mySourceData );
}
else
{
// Get the event log corresponding to the existing source.
myLogName = EventLog::LogNameFromSourceName( sourceName, "." );
}
// Register the localized name of the event log.
// For example, the actual name of the event log is "myNewLog," but
// the event log name displayed in the Event Viewer might be
// "Sample Application Log" or some other application-specific
// text.
EventLog^ myEventLog = gcnew EventLog( myLogName,".",sourceName );
if ( messageFile->Length > 0 )
{
myEventLog->RegisterDisplayName( messageFile, DisplayNameMsgId );
}
}
static void CreateEventSourceSample1(string messageFile)
{
string myLogName;
string sourceName = "SampleApplicationSource";
// Create the event source if it does not exist.
if(!EventLog.SourceExists(sourceName))
{
// Create a new event source for the custom event log
// named "myNewLog."
myLogName = "myNewLog";
EventSourceCreationData mySourceData = new EventSourceCreationData(sourceName, myLogName);
// Set the message resource file that the event source references.
// All event resource identifiers correspond to text in this file.
if (!System.IO.File.Exists(messageFile))
{
Console.WriteLine("Input message resource file does not exist - {0}",
messageFile);
messageFile = "";
}
else
{
// Set the specified file as the resource
// file for message text, category text, and
// message parameter strings.
mySourceData.MessageResourceFile = messageFile;
mySourceData.CategoryResourceFile = messageFile;
mySourceData.CategoryCount = CategoryCount;
mySourceData.ParameterResourceFile = messageFile;
Console.WriteLine("Event source message resource file set to {0}",
messageFile);
}
Console.WriteLine("Registering new source for event log.");
EventLog.CreateEventSource(mySourceData);
}
else
{
// Get the event log corresponding to the existing source.
myLogName = EventLog.LogNameFromSourceName(sourceName,".");
}
// Register the localized name of the event log.
// For example, the actual name of the event log is "myNewLog," but
// the event log name displayed in the Event Viewer might be
// "Sample Application Log" or some other application-specific
// text.
EventLog myEventLog = new EventLog(myLogName, ".", sourceName);
if (messageFile.Length > 0)
{
myEventLog.RegisterDisplayName(messageFile, DisplayNameMsgId);
}
}
Public Shared Sub CreateEventSourceSample1(ByVal messageFile As String)
Dim myLogName As String
Dim sourceName As String = "SampleApplicationSource"
' Create the event source if it does not exist.
If Not EventLog.SourceExists(sourceName)
' Create a new event source for the custom event log
' named "myNewLog."
myLogName = "myNewLog"
Dim mySourceData As EventSourceCreationData = New EventSourceCreationData(sourceName, myLogName)
' Set the message resource file that the event source references.
' All event resource identifiers correspond to text in this file.
If Not System.IO.File.Exists(messageFile)
Console.WriteLine("Input message resource file does not exist - {0}", _
messageFile)
messageFile = ""
Else
' Set the specified file as the resource
' file for message text, category text and
' message parameters strings.
mySourceData.MessageResourceFile = messageFile
mySourceData.CategoryResourceFile = messageFile
mySourceData.CategoryCount = CategoryCount
mySourceData.ParameterResourceFile = messageFile
Console.WriteLine("Event source message resource file set to {0}", _
messageFile)
End If
Console.WriteLine("Registering new source for event log.")
EventLog.CreateEventSource(mySourceData)
Else
' Get the event log corresponding to the existing source.
myLogName = EventLog.LogNameFromSourceName(sourceName,".")
End If
' Register the localized name of the event log.
' For example, the actual name of the event log is "myNewLog," but
' the event log name displayed in the Event Viewer might be
' "Sample Application Log" or some other application-specific
' text.
Dim myEventLog As EventLog = New EventLog(myLogName, ".", sourceName)
If messageFile.Length > 0
myEventLog.RegisterDisplayName(messageFile, DisplayNameMsgId)
End If
End Sub
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
Use the CategoryCount and CategoryResourceFile properties to write events with localized category strings. The Event Viewer displays the category for an event entry if you supply a category when you write the event. Event log categories are application-defined strings that help filter events, or provide further information on the event. For example, your application can define separate categories for different components or different operations.
Event categories are optional; if your application does not use categories, do not set the CategoryCount and CategoryResourceFile properties.
For details about defining event messages and building event resource files, see the Message Compiler article in the Platform SDK documentation.
