Maximum PC

Does data in DataGridView have to be static? As in, The personal project I'm working on now will scan a network, And display the active IP in one column and CPU name in the other column. But I'm having a hard time figuring one thing out, as in does the data being displayed in the datagrid view have to come from a static source? like, would I have to tell my program to dump the information returned into a database and then have the datagridview display that information? Or can it be done on the fly, as in each time a new set of info is found for a pc, it can be added in memory to the datagridview with a new row?

question number 2.

Progressbars: I have found plenty of tutorials for progress bars such as



I see that that block of code would force me click a button 100 times to complete the bar. And that same code can also be put into a timer to make it take 100 seconds to complete the bar. What I don't under stand is how to make that work for say, a file download or a process taking place in the program. For a file download would the code work



As a very rough example above, would that in theory be how one would have to do it? And that leads me to wonder since that could not be put on a timer, would that have to be put on some sort of background worker for the program?

Wow, that's a complicated project!

1. Does a datagridview need a static datasource? Yes and no. DataGridViews require that you pass a data source to it, whether you pass an IEnumerable collection, a Collection of a type or a DataSet, it must be a collection. Your project is a tad more complicated because you'll need to use threads to scan the network, possibly a delegate to trigger a callback/event (i.e., OnAfterNetworkScan -> do something), and a locked resource (i.e. list/collection). Since I'm not a threading guru, please take this with a grain of salt, but once you trigger the callback/event you'll need to update the data source and rebind it to the DataGridView.



Again, it's a tad more complicated. You can't simply put it inside a background thread that steps the counter. Most file downloads are synchronous (i.e., it blocks a thread to do its work, so the app has to wait). C#/.NET has an asynchronous mechanism for almost all Stream/WebRequests. The reason for this is that while most I/O can be done synchronously, sometimes, you can't have the app block a thread for various reasons. When you want the current thread to continue without being blocked, you call an asynchronous method. They typically begin with Begin* and End*. They're a pain to use and a freakin' pain to understand. I don't use them, I hate them and I'm awaiting .NET 4.5 for Microsoft to make it simpler by adding the await keyword to the syntax list. I mean, seriously, when you look into asynchronicity in your app, you're looking at callbacks as tall as the Sears Tower.

If you're really intersted in learning these things, pick up a book on threading, threading patterns, asynchronous programming and events.