Advanced Win32 Techniques in .NET

Generating QR Code in .NET Advanced Win32 Techniques

Advanced Win32 Techniques
QR Printer In VS .NET
Using Barcode drawer for .NET framework Control to generate, create QR Code image in Visual Studio .NET applications.
www.OnBarcode.com
Quick Response Code Decoder In .NET
Using Barcode reader for .NET framework Control to read, scan read, scan image in .NET framework applications.
www.OnBarcode.com
Private Sub EntryWritten(ByVal sender As Object, _ ByVal e As System.Diagnostics.EntryWrittenEventArgs) Filter out events from sources we aren t interested in. If e.Entry.Source = MSSQLServer Then (GetEntryInfo has been defined previously.) Console.WriteLine(GetEntryInfo(e.Entry)) End If End Sub
Bar Code Printer In .NET
Using Barcode creation for Visual Studio .NET Control to generate, create barcode image in VS .NET applications.
www.OnBarcode.com
Recognizing Bar Code In .NET
Using Barcode recognizer for .NET framework Control to read, scan read, scan image in Visual Studio .NET applications.
www.OnBarcode.com
As the preceding code shows, the EntryWritten event fires when any source writes to the specified log, regardless of the source argument you might have specified in the constructor of the EventLog component. For this reason, you have to manually filter out events from sources you aren t interested in.
QR Code JIS X 0510 Printer In Visual C#.NET
Using Barcode printer for .NET framework Control to generate, create QR image in .NET applications.
www.OnBarcode.com
Generate QR Code ISO/IEC18004 In .NET Framework
Using Barcode generation for ASP.NET Control to generate, create Denso QR Bar Code image in ASP.NET applications.
www.OnBarcode.com
Writing Event Log Entries
Making QR-Code In VB.NET
Using Barcode generation for .NET framework Control to generate, create Quick Response Code image in VS .NET applications.
www.OnBarcode.com
Barcode Generation In .NET
Using Barcode generation for VS .NET Control to generate, create bar code image in Visual Studio .NET applications.
www.OnBarcode.com
The EventLog class makes it simple to write to an event log as well, even though an application can write to an event log only if it s registered as a valid event source.
GS1 DataBar Drawer In .NET Framework
Using Barcode generation for VS .NET Control to generate, create GS1 DataBar Truncated image in .NET applications.
www.OnBarcode.com
Data Matrix ECC200 Creation In VS .NET
Using Barcode generator for .NET Control to generate, create ECC200 image in VS .NET applications.
www.OnBarcode.com
Registering Your Application as an Event Source
Encode EAN 13 In VS .NET
Using Barcode generation for VS .NET Control to generate, create EAN 13 image in .NET framework applications.
www.OnBarcode.com
Draw Identcode In VS .NET
Using Barcode creator for VS .NET Control to generate, create Identcode image in .NET framework applications.
www.OnBarcode.com
You can register your application as a valid event source by means of the CreateEventSource shared method of the EventLog class. This method takes the source name (the string that will identify messages from this application in the log) and the name of the log your application will write to (typically the Application log):
Code 128B Drawer In None
Using Barcode printer for Office Word Control to generate, create Code 128B image in Office Word applications.
www.OnBarcode.com
Drawing Barcode In Java
Using Barcode generation for Eclipse BIRT Control to generate, create barcode image in BIRT applications.
www.OnBarcode.com
Register your demo app as an event source. EventLog.CreateEventSource( DemoApp", Application )
Make QR-Code In VB.NET
Using Barcode printer for Visual Studio .NET Control to generate, create Denso QR Bar Code image in VS .NET applications.
www.OnBarcode.com
Reading Data Matrix In Java
Using Barcode decoder for Java Control to read, scan read, scan image in Java applications.
www.OnBarcode.com
If you skip this registration step, however, your application will be registered on the fly when you write the first entry to the log. The DeleteEventSource shared method unreg isters an event source. Notice that you don t have to specify the name of the log because the system can deduce it from the name of the source:
USS Code 39 Generation In Visual Studio .NET
Using Barcode maker for Reporting Service Control to generate, create USS Code 39 image in Reporting Service applications.
www.OnBarcode.com
EAN / UCC - 13 Creation In VS .NET
Using Barcode generation for Reporting Service Control to generate, create EAN 128 image in Reporting Service applications.
www.OnBarcode.com
Delete this event source. EventLog.DeleteEventSource( DemoApp )
EAN 13 Reader In VB.NET
Using Barcode reader for VS .NET Control to read, scan read, scan image in .NET framework applications.
www.OnBarcode.com
GTIN - 13 Printer In None
Using Barcode generator for Online Control to generate, create EAN13 image in Online applications.
www.OnBarcode.com
The DeleteEventSource method can be useful when you want to change the destina tion log for events written by your application. Deleting an event source doesn t remove the existing log entries associated with that source.
Creating a Custom Log
Creating a custom log is much simpler than you probably think it is, and you might argue that it s a bit too simple. In fact, if the log name that you pass to the second argu ment of the CreateEventSource method or to the EventLog s constructor doesn t corre spond to an existing log, a new log is automatically created for you. This means that
Part IV:
Win32 Applications
you might accidentally create new logs just because you misspelled the name of the log in one of these calls:
Create a new custom log named MyLog. EventLog.CreateEventSource( MyDemoApp", MyLog )
Only the first eight characters of the log name are significant; if the first eight characters in your custom log s name match the name of an existing log (as in ApplicationNew), you won t create a new log. You can create a custom log on a remote machine by pass ing a third argument to the CreateEventSource method, provided you have sufficient administrative rights on the remote system. You delete a custom log using the EventLog.Delete shared method. Pay attention when using this method because it deletes all the event entries and all the event sources asso ciated with the deleted log. Also notice that you might accidentally delete one of the predefined system logs, in which case you might have to reinstall the operating system:
Delete the custom log. EventLog.Delete( MyLog )
A less radical operation consists of removing all the entries from a given log, which you can do by invoking the Clear method:
Dim evLog As New EventLog( MyLog", . ) evLog.Clear()
Clearing an event log periodically possibly after saving its current contents to a file from inside the Event Viewer utility helps you avoid problems when the event log becomes full. (The default behavior when this happens is to start overwriting the oldest entries with the newest entries.) By default, the Application, System, and Security logs can grow up to 4992 KB, whereas custom logs have a default maximum size of 512 KB. You can change these default values and modify the default behavior from inside the Event Viewer utility.
Copyright © OnBarcode.com . All rights reserved.