Use the .NET FileSystemWatcher object to monitor directory changes in C#
Source: Zach Smith
There are many instances that require systems to perform certain tasks when files or directories are created or modified. One of the more interesting objects included in the Microsoft .NET Framework class library is the System.IO.FileSystemWatcher. This object allows you to be notified when certain events occur in a directory, such as file creation, deletion, or modification. Zach Smith explains how to use the FileSystemWatcher object and demonstrates it in a sample application.
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