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Integrate QR Code ISO/IEC18004 in .NET Objective 3.2

n Note This chapter does not follow an instructional format as the subsequent chapters do. Instead I ll

; The last little bit of SEH setup to record where the try block starts ; on the stack and the code is entering the try block. MOV AND DWORD PTR [EBP-18h] , ESP DWORD PTR [EBP-4] , 0

The Web Administration Tool provides a visual interface for creating associations between users and roles. If necessary, you can instead perform this task programmatically by calling various role manager methods. The following code demonstrates how to create the Admin and Guest roles and populate them with usernames:

Now ToString is called on the unboxed value type instance v, and a String is returned . String objects are already reference types and can simply be passed to the Concat method without requiring any boxing . Let s look at yet another example that demonstrates boxing and unboxing:

On the File Screen Policy page, you can apply a le screen to limit the types of les the shared folder can contain. Choose a template from the drop-down list (as shown in Figure 10-5) and a summary of the le screen properties appears. Click Next.

Title Overlay Windows Movie Maker includes a titles/credits editor. If you use it to create titles that appear superimposed on the video of your movie, these titles are represented on the Title Overlay track of the timeline. You can also use the editor to generate a title that appears at the beginning of your movie or credits that appear at the end, those items are represented on the Video track of the timeline. (For more about titles, see Creating Titles and Credits, later in this chapter.)

The .NET server range consists of a set of rebranded and updated versions of existing Microsoft server products. The .NET server functionality covers everything from operating systems and relational databases to process integration and communications. The range currently includes the following products:

Figure 9-1 shows the execution plan for the query in Listing 9-1.

Depending on where the state lives, you can use transactions which ensure that all state is modified or no state is modified . If the data is in a database, for example, transactions work well . Windows also now supports transacted registry and file operations (on an NTFS volume only) and so you might be able to use this; however the .NET Framework doesn t expose this functionality directly today . You will have to P/Invoke to native code to leverage it . See the System.Transactions.TransactionScope class for more details about this . You can design your methods to be more explicit . For example, the Monitor class is typically used for taking/releasing a thread synchronization lock as follows:

Interval You can set how often the Performance console queries the system for what you want to monitor. The system doesn t continuously monitor for the counters you want; rather, it performs samples over a certain amount of time. The longer the interval, the less accurate the sample is because it is being sampled less. The shorter the interval, the more accurate the sample is, but the more the proces sor is used when getting the sample. Units You can specify the units in time to collect samples. For instance, you might not want to sample every 5 seconds; instead, you might want to sample every 30 seconds. Again, if you reduce the frequency of sampling, you ll use fewer processor cycles, but you will be less accurate. Run As You can sample the counters by selecting either the System account or another account of your choice. Occasionally, counters can be user-specific, which is necessary. However, for monitoring network-related counters, the System account has access to what it needs to perform the work.

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