net qr code reader open source FIguRE 4-8 Allocating M3 s local variables on the thread s stack in .NET

Draw qrcode in .NET FIguRE 4-8 Allocating M3 s local variables on the thread s stack

When the M2 method starts to execute, its prologue code allocates memory for the local length and tally variables from the thread s stack (see Figure 4-5) . Then the code inside method M2 executes . Eventually, M2 gets to its return statement, which causes the CPU s instruction pointer to be set to the return address in the stack, and M2 s stack frame is unwound so that it looks the way it did in Figure 4-3 . At this point, M1 is continuing to execute its code that immediately follows the call to M2, and its stack frame accurately reflects the state needed by M1 .

How secret are your secrets We all know how important it is to encrypt information that is sensitive, whether it is stored in a database or a disk file, passed over the network (especially the Internet), or even sitting around in memory. Handing over a list of your customers credit card numbers to some geek sitting in his bedroom hacking your online store is not a great way to build customer confidence. Neither is allowing some disenfranchised administrator to leave your company with a plain-text copy of all your trading partners network passwords. The trouble is that writing all that extra code from scratch to perform reliable and secure encryption is complicated and soaks up valuable development time. Even the names of the encryption algorithms are impenetrable, such as AES, 3DES, and RC5. And when it comes to hashing algorithms, there s even more of an assortment. How do you implement routines to use the HMAC, MD5, RIPEMD, and SHA algorithms The Microsoft .NET Framework provides a range of managed code hashing and encryption mechanisms, but you still need to write a good deal of code to use them. Thankfully, the Cryptography Application Block makes it all very much easier. Like all of the other application blocks in Enterprise Library, the Cryptography block is completely configurable and manageable, and offers a wide range of hashing and encryption options using many of the common (and some not so common) algorithms.

To test the function, run the following code, which returns an auxiliary table with 10 numbers:

Although this is a simple example, you should still be able to see the enormous benefit you get from encapsulating the data fields . You should also be able to see how easy it is to make read-only or write-only properties: just don t implement one of the accessor methods . Alternatively, you could allow only derived types to modify the value by marking the SetXxx method as protected .

Add a GridView control to the page. Set the DataSourceID property to point to the EntityDataSource created previously. Define bound columns and change the HeaderText for each field in the result set. Enable AllowPaging and AllowSorting. Add a HyperLinkField to the GridView to call orders.aspx and pass the customer ID as a query string parameter.

This solution uses CASE expressions in a more sophisticated way . Each column and sort direction combination is treated with its own CASE expression . Only one of the CASE expressions yields TRUE for all rows, given the column name and sort direction that particular CASE expression is looking for . All other CASE expressions return NULL for all rows . This means that only one of the CASE expressions the one that looks for the given column name and sort direction affects the order of the output .

W. X . Y. Z Example: 131.107.16.200

The .find() function is similar to a sub-search in that it allows you to search through your result set. This code first finds everything inside a <div/> tag with the ID of div1 and then selects only those elements that are defined as <h2/>.

Table 8-8