c# code 39 barcode generator C HA PTER 11 USE O F XML I N T HE .NET F RAME WO RK in visual C#

Encoder barcode code39 in visual C# C HA PTER 11 USE O F XML I N T HE .NET F RAME WO RK

he service layer of an application represents the suite of operations that can be performed with that application. This layer is often broken down into several business domains. The service layer typically serves several purposes: Exposing the functionality of the application to the outside world Grouping together logically related functionality Implementing business logic Providing the boundary for transactional operations

Figure 2-21. Expression Editor As we go through various reporting projects in this book, you ll see many examples using the Expression Editor.

The firewall located on the Sharing pane in Tiger is based on the open source program ipfw. Ipfw is short for Internet Protocol Firewall and can also be used with Leopard and Snow Leopard. The ipfw program has the ability to configure the port-based firewall in OS X, different from the application layer firewall in that rather than relying on application signatures it monolithically blocks specified ports. However, there is a rather steep learning curve when configuring the firewall with the ipfw interface for the first time, especially if you aren t very experienced with BSD. But learning curves are good. They offer you a chance to know more about the firewall on your system, what it is doing, and the key factors you should consider to make your network more secure. You also have the opportunity to get to know more about the inner workings of your system and how the different pieces to the security puzzle fit together. Because ipfw works at the kernel level, or innermost level, of the operating system, it has particular security requirements and requires that you run it from a superuser account. This is accomplished by using the sudo command to issue commands and create rules for it. Applications such as LimeWire or Samba (the Windows file-sharing component of Mac OS X) cannot override rules enforced by ipfw because of the secure nature of the command. The official syntax for the base ipfw toolkit is as follows:

These hexadecimal sequences in the logs can help decipher why a crash occurred if foul play is suspected. Nine times out of ten, rather than confirm irregular activity, you will instead find that there is actually a technical problem that caused the crash.

An instance of SQL Server installed on a server with no instance name specified. The name of the instance is thus just the computer name. Multiple instances of SQL Server can be installed on the same computer; however, only one can be the default instance. The other instances are referred to as named instances and have the form computername\instancename.

In some older F# code, you see the frequent use of underscores to qualify some names. For example: Suffixes such as _left and _right Prefix verbs such as add_, remove_, try_, and is_, do_ Prefix connectives such as to_, of_, from_, and for_

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Event handlers are methods that are executed when a given event is triggered. You can define event handlers either in the XAML markup itself or in managed code. The following exercises will demonstrate how to define event handlers in both ways.

RFC 2307 is a set of standards laid out for Unix-style operating systems to leverage LDAP as a centralized directory services solution. In fact, many of the attributes from Open Directory are taken directly from the standards laid out in RFC 2307. There is no

The IConstructionReturnMessage interface is an implementation of IMethodReturnMessage and provides the client with results of the activation of a client-activated object. Therefore, it is used by the infrastructure for checking the success of the creation process as well as retrieving context information created by the activator during the creation process. IConstructionReturnMessage defines no additional properties or methods in the current version of the .NET Framework. More information on MSDN: http://msdn.microsoft.com/library/en-us/cpref/html/ frlrfsystemruntimeremotingactivationiconstructionreturnmessageclasstopic.asp