s DATA ACCESS AND SECURITY in visual C#

Generating pdf417 in visual C# s DATA ACCESS AND SECURITY

In silent install, there is also automation for performing an uninstall of the application using the sllauncher.exe utility. As shown, simply issue the origin command in one line to uninstall the application that we just installed: "%ProgramFiles(x86)%\Microsoft Silverlight\sllauncher.exe" /uninstall /origin:"http://localhost:2760/ClientBin/AdvanceFeaturesDemoApp.xap"

In the sample Simple2.il presented in the previous chapter, the methods of console input/ output were called four times (one time for input and three times for output). And every time I had to type [mscorlib]System.Console::WriteLine or [mscorlib]System.Console::ReadLine. In ILAsm 1.0 and 1.1 I had no choice, but in ILAsm 2.0 I can use aliasing, assigning new short names to methods, classes, and so on. Listing 3-1 shows the simple sample from the previous chapters with aliasing (source file Simple3.il). And, by the way, while at it, let s get rid of unnecessary default declarations. Listing 3-1. Simple3.il with Aliasing //----------- Program header .assembly extern mscorlib { auto } .assembly OddOrEven { } .module OddOrEven.exe //----------- Aliasing .typedef [mscorlib]System.Console as TTY .typedef method void TTY::WriteLine(string) as PrintLine //----------- Class Declaration .class public Odd.Or.Even { //------------ Field declaration .field public static int32 val //------------ Method declaration .method public static void check( ) { .entrypoint .locals init (int32 Retval) AskForNumber: ldstr "Enter a number" call PrintLine .try {

bool IsQueryCompleted() { return result->IsCompleted; } // This function gets called when the asynchronous call // completes. void ProcessResult(IAsyncResult^ result) { // Retrieve the delegate. QueryFunc^ caller = (QueryFunc^) result->AsyncState; // Get the data back (fill in DataSet parameter). caller->EndInvoke(result); Console::WriteLine(m_r->Value); } void UseData() { // Do something... } }; int main() { Document doc("Old Value"); doc.InitiateQuery("SELECT * FROM Plants WHERE Plant.Genus = 'Lycopersicon'"); // Do other work while the query executes. // Poll for completion. while (! doc.IsQueryCompleted() ) { Thread::Sleep(100); } // Do work with the data. doc.UseData(); } Here is the output of Listing 7-14: Old Value New Value

Figure 1-15. Passing a DataSet between the Business and Data Access layers This approach has the maintenance and code-reuse flaws that I ve talked about, but the fact is that it gives pretty good performance in most cases. Also, it doesn t hurt that most programmers are pretty familiar with the idea of writing code to manipulate a DataSet, so the techniques involved are well understood, thus speeding up development. A decision to stick with an object-oriented approach should be undertaken carefully. It s all too easy to compromise the object-oriented design by taking the data out of the objects running on one machine, sending the raw data across the network, and allowing other objects to use that data outside the context of the objects and business logic. Such an approach would break the encapsulation provided by the logical Business layer.

namespace UsingStatement { class Program { static void Main( ) { // using statement using (TextWriter tw = File.CreateText("Lincoln.txt") ) { tw.WriteLine("Four score and seven years ago, ..."); } // using statement using (TextReader tr = File.OpenText("Lincoln.txt")) { string InputString; while (null != (InputString = tr.ReadLine())) Console.WriteLine(InputString); } } } } This code produces the following output: Four score and seven years ago, ...

On your iPod touch you have the option of setting a four-digit passcode that prevents unauthorized access to your iPod touch and your information. If the wrong passcode is entered, however, even you won t be able to access your information, so it's a good idea to use a code you ll easily remember. TIP: If you use Apple's MobileMe service described in 4: "Other Sync Methods," you can use the MobileMe web site to set a passcode on your iPod touch without even touching the iPod touch, by using the remote-lock feature. You can also remotely erase all data on your iPod touch from the MobileMe site with the remote-wipe feature. To set a passcode to lock your iPod touch, follow these steps.

If you were to execute the preceding example as a less-privileged user (OPS$TKYTE has been granted the DBA role for purposes of this book), you would see instead:

The code stops users from moving the pivot table fields to a different location in the PivotTable Field List. It also prevents adding or removing fields in the pivot table layout. To allow layout changes again, create and run a similar macro that sets the DragTo properties to True. In addition to the security features discussed in this and previous sections, you can programmatically control access to the following features: PivotTable Field List Field Settings Refresh Ribbon s PivotTable Tools contextual tabs Show Details The following macro turns off each of these features. Store the macro on a regular code module. Sub RestrictPTChanges() Dim pt As PivotTable Application.EnableEvents = False Set pt = ActiveSheet.PivotTables(1)

An XML processing instruction is used to supply additional data about how an XML document should be used or interpreted. Most commonly, processing instructions are used to associate a style sheet with the XML document. You can include a processing instruction using the XProcessingInstruction constructor, which takes two string parameters a target and a data string. If the processing instruction takes multiple data parameters, those parameters must be included in the second parameter string of the XProcessingInstruction constructor, as shown in the following constructor code. Notice that in this example, the second parameter is a verbatim string, and literal double quotes inside the string are represented by sets of two contiguous double quote marks. new XProcessingInstruction( "xml-stylesheet", @"href=""stories"", type=""text/css""")