How It Works
As we start, the application has disabled almost everything except the starting control. You create the record file by choosing the date (see Figure 3). By default, we store this file in My Documents. I prefer to restrict where users can place files. You don’t want hackers using your ASP web application to overwrite or view important system files. Most Pocket PC applications aren’t intended to be multiuser or used over a network, but security is still an important consideration. Hard-coding the directory is an exercise left to the student.
Figure 3 Emulator and app at work.
After you select the date, a dialog box shows where the file is being saved. Now that the set box is disabled, your only option is the Open button, to select the list of students. Select the text file with the names, and confirm that it’s the file you want to open.
Three names pop up at a time. Click the check box of each absent student (see Figure 4). Click the Next button, and you get a dialog box indicating which names were clicked. Code a confirmation question so that you can clear mistaken clicks.
So life goes on, one Next button at a time, until the final End menu click. Seems inconsistent, doesn’t it? Progress with a button, yet end with a menu? These are great questions for students to resolve.
Figure 4 Noting absences.
A simple app that comes up and lets you quickly check attendance. It reads and writes text files. It lets you compare Compact Framework coding to .NET Framework coding. It even lets you do all of this without purchasing a deployment device. Now what can you do with this information?
Make money? Do you have a smart phone? Do other people you know have one? The same things you’ve learned here allow you to code for a very large number of users, some of whom may not find your application widely available. It took me only a few hours to code this app, because it’s basic .NET code. So consider buying an iPAQ on eBay, a decent copy of Visual Studio, maybe a smart phone, and see what happens.
I’ve noticed that it’s difficult finding simple details on text-file operations. In my next article, I’ll cover that topic in detail.