Skip to main content

C# Snippet Tutorial - Get File Listings [Beginner]


Ok, so can you even begin to tell me how many files you have on your computer? I can't either. There are so many reasons you could need to get file listings in C#, and thanks to the System.IO namespace, doing so is just about as easy as including the namespace itself. Really all you need to do is create a variable, then a loop.

So all the magic happens due to a couple of nice and simple classes in the System.IO namespace, called DirectoryInfo and FileInfo. Really, with these two classes you can do a lot of cool stuff, directory and file wise that is. Not only do these classes make file and directory listing really simple, but they are actually more powerful than they seem.

Anyway, in order to get started, you must first include the System.IO namespace, mainly because it is not used by default. So add it to the top of your code. Next we are going to make a new DirectoryInfo instance, and in this case we are using the root drive of C:\, so your code should look like:
DirectoryInfo fileListing = new DirectoryInfo("C:\\");
 
This code does exactly what you would think, it takes the directory and allows you to get all kinds of information about it. You can use this one variable to find out all kinds of things, anything from directory permissions to the last modified date. Now, this little snippet will only cover the basics, but when you are looking at more, just remember listing files is only the simplest of things you can do.

Now that we have our DirectoryInfo object, we can loop through all the files in that directory and do whatever we like with them. In this case, we are just going to fill a listbox with the full file path. To do this, all we need to do is call the GetFiles() method, which returns an array of FileInfo objects. Each FileInfo has a ton of information on each file, but all we really need is the name right now. So our final code might look something like:
DirectoryInfo fileListing = new DirectoryInfo("C:\\");

foreach (FileInfo file in fileListing.GetFiles())
{
  listBox1.Items.Add(fileListing.ToString() + file.Name);
}
 
Super simple, but lets be honest with ourselves, how often do you want all the files in a directory? Not very often I would think. Luckily, the GetFiles() method has an argument to limit what files you get. This argument is just a string that you can add a search pattern to. So say we want to search for .txt files. Our updated code would look like so:
DirectoryInfo fileListing = new DirectoryInfo("C:\\");

foreach (FileInfo file in fileListing.GetFiles("*.txt"))
{
  listBox1.Items.Add(fileListing.ToString() + file.Name);
}
 
The one downside to using the search pattern is that you can only use one of them. As far as I know you can only use one search pattern in the string, so in order to get multiple file types, you have to call the method again with a different pattern. That being said, it is not too much of an inconvenience being as easy as it is.

So that is pretty much how you can get the files in a current directory. Super simple and super fast. You can do all kinds of things with the DirectoryInfo and FileInfo classes, so I would check them out if you can.

Comments

Popular posts from this blog

C# Snippet - Shuffling a Dictionary [Beginner]

Randomizing something can be a daunting task, especially with all the algorithms out there. However, sometimes you just need to shuffle things up, in a simple, yet effective manner. Today we are going to take a quick look at an easy and simple way to randomize a dictionary, which is most likely something that you may be using in a complex application. The tricky thing about ordering dictionaries is that...well they are not ordered to begin with. Typically they are a chaotic collection of key/value pairs. There is no first element or last element, just elements. This is why it is a little tricky to randomize them. Before we get started, we need to build a quick dictionary. For this tutorial, we will be doing an extremely simple string/int dictionary, but rest assured the steps we take can be used for any kind of dictionary you can come up with, no matter what object types you use. Dictionary < String , int > origin = new Dictionary < string , int >(); ...

C# WPF Printing Part 2 - Pagination [Intermediate]

About two weeks ago, we had a tutorial here at SOTC on the basics of printing in WPF . It covered the standard stuff, like popping the print dialog, and what you needed to do to print visuals (both created in XAML and on the fly). But really, that's barely scratching the surface - any decent printing system in pretty much any application needs to be able to do a lot more than that. So today, we are going to take one more baby step forward into the world of printing - we are going to take a look at pagination. The main class that we will need to do pagination is the DocumentPaginator . I mentioned this class very briefly in the previous tutorial, but only in the context of the printing methods on PrintDialog , PrintVisual (which we focused on last time) and PrintDocument (which we will be focusing on today). This PrintDocument function takes a DocumentPaginator to print - and this is why we need to create one. Unfortunately, making a DocumentPaginator is not as easy as...

C# WPF Tutorial - Implementing IScrollInfo [Advanced]

The ScrollViewer in WPF is pretty handy (and quite flexible) - especially when compared to what you had to work with in WinForms ( ScrollableControl ). 98% of the time, I can make the ScrollViewer do what I need it to for the given situation. Those other 2 percent, though, can get kind of hairy. Fortunately, WPF provides the IScrollInfo interface - which is what we will be talking about today. So what is IScrollInfo ? Well, it is a way to take over the logic behind scrolling, while still maintaining the look and feel of the standard ScrollViewer . Now, first off, why in the world would we want to do that? To answer that question, I'm going to take a an example from a tutorial that is over a year old now - Creating a Custom Panel Control . In that tutorial, we created our own custom WPF panel (that animated!). One of the issues with that panel though (and the WPF WrapPanel in general) is that you have to disable the horizontal scrollbar if you put the panel in a ScrollV...