Programmers Heaven: C# School

We have written the following code on the ‘Go’ button’s event handler:

private void btnGo_Click(object sender, System.EventArgs e)

{

}

Here we have simply used the properties of the FileInfo class to retrieve and print some information about a file. When I executed this program on my system, I got the following output:

Note: Before executing this program, I changed the attributes of file ‘C:\C-Sharp.txt’ to Readonly, Hidden and Archive using Windows Explorer.

Manipulating Directories (folders) using System.IO.Directory and System.IO.DirectoryInfo classes

Similar to the File and FileInfo classes we can perform several operations on directories using the Directory and DirectoryInfo classes. Again it is worth-noting that the System.IO.Directory class contains static methods while the System.IO.DirectoryInfo class contains instance members to perform various tasks on directories.

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System.IO.Directory class

A review of static methods of the Directory class is presented in the following table:

Creating, deleting and checking for the existence of directories

Some code that demonstrates how to perform the above operations is shown below.

Again, the code simply calls the various static methods of the Directory class to perform these operations. One thing to note here is that we have passed the path-string and a true value to the Directory.Delete() method. Passing the true value as the second parameter tells the runtime environment (CLR) to remove the directory recursively i.e. not only deletes the files in this directory but also delete the files and directories contained in its sub-directories and so on.

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Getting the contents (files and sub-directories) of a directory

The Directory class exposes three methods to retrieve the contents of a directory. Directory.GetDirectories() returns a list of all the sub-directories of the specified directory, Directory.GetFiles() returns a list of all the files in the specified directory and Directory.GetFileSystemEntries() returns a list of all the files and sub-directories contained in the specified directory. Let’s get a list of the contents of the Windows folder of your system.

private void btnGo_Click(object sender, System.EventArgs e)

{

// get the path of Windows Folder's System Folder

string winFolder = Environment.GetFolderPath(Environment.SpecialFolder.System); // Separate the Windows Folder

winFolder = winFolder.Substring(0, winFolder.LastIndexOf('\\'));

string[] fileSystemEntries = Directory.GetFileSystemEntries(winFolder); string[] files = Directory.GetFiles(winFolder);

string[] directories = Directory.GetDirectories(winFolder);

// show windows folder path

lbx.Items.Add("Address of Windows Folder: " + winFolder);

//show files/folder in windows folder lbx.Items.Add("");

lbx.Items.Add("File System Entries (files/folder) in the Windows Folder: "); foreach(string fileSystemEntry in fileSystemEntries)

{

lbx.Items.Add("\t" + fileSystemEntry);

}

//show files in windows folder

lbx.Items.Add("");

lbx.Items.Add("Files in the Windows Folder: "); foreach(string file in files)

{

lbx.Items.Add("\t" + file);

}

// show folder in windows folder lbx.Items.Add("");

lbx.Items.Add("Directories in the Windows Folder: "); foreach(string directory in directories)

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{

lbx.Items.Add("\t" + directory);

}

}

And when I executed the above program on my system, I got the following result:

System.IO.DirectoryInfo class

The System.IO.DirectoryInfo class is also used to perform different operations on directories. Unlike the Directory class, we need to create an object of the DirectoryInfo class to use its services. A review of some of the important methods and properties of the DirectoryInfo class is presented in the following table: