Occurs when a file or directory in the specified FileSystemWatcher.Path is deleted.
Some common occurrences, such as copying or moving a file or directory, do not correspond directly to an event, but these occurrences do cause events to be raised. When you copy a file or directory, the system raises a FileSystemWatcher.Created event in the directory to which the file was copied, if that directory is being watched. If the directory from which you copied was being watched by another instance of System.IO.FileSystemWatcher, no event would be raised. For example, you create two instances of System.IO.FileSystemWatcher. FileSystemWatcher1 is set to watch "C:\My Documents", and FileSystemWatcher2 is set to watch "C:\Your Documents". If you copy a file from "My Documents" into "Your Documents", a FileSystemWatcher.Created event will be raised by FileSystemWatcher2, but no event is raised for FileSystemWatcher1. Unlike copying, moving a file or directory would raise two events. From the previous example, if you moved a file from "My Documents" to "Your Documents", a FileSystemWatcher.Created event would be raised by FileSystemWatcher2 and a FileSystemWatcher.Deleted event would be raised by FileSystemWatcher1.
Common file system operations might raise more than one event. For example, when a file is moved from one directory to another, several FileSystemWatcher.OnChanged(FileSystemEventArgs) and some FileSystemWatcher.OnCreated(FileSystemEventArgs) and FileSystemWatcher.OnDeleted(FileSystemEventArgs) events might be raised. Moving a file is a complex operation that consists of multiple simple operations, therefore raising multiple events. Likewise, some applications (for example, antivirus software) might cause additional file system events that are detected by System.IO.FileSystemWatcher.
The order in which the FileSystemWatcher.Deleted event is raised in relation to the other System.IO.FileSystemWatcher events may change when the FileSystemWatcher.SynchronizingObject property is not null.