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FileSystemEventArgs Class

 
System_CAPS_noteNote

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Provides data for the directory events: Changed, Created, Deleted.

Namespace:   System.IO
Assembly:  System (in System.dll)

System.Object
  System.EventArgs
    System.IO.FileSystemEventArgs
      System.IO.RenamedEventArgs

public class FileSystemEventArgs : EventArgs

NameDescription
System_CAPS_pubmethodFileSystemEventArgs(WatcherChangeTypes, String, String)

Initializes a new instance of the FileSystemEventArgs class.

NameDescription
System_CAPS_pubpropertyChangeType

Gets the type of directory event that occurred.

System_CAPS_pubpropertyFullPath

Gets the fully qualifed path of the affected file or directory.

System_CAPS_pubpropertyName

Gets the name of the affected file or directory.

NameDescription
System_CAPS_pubmethodEquals(Object)

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_protmethodFinalize()

Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)

System_CAPS_pubmethodGetHashCode()

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_protmethodMemberwiseClone()

Creates a shallow copy of the current Object.(Inherited from Object.)

System_CAPS_pubmethodToString()

Returns a string that represents the current object.(Inherited from Object.)

The FileSystemEventArgs class is passed as a parameter to event handlers for these events:

The Changed event occurs when changes are made to the size, system attributes, last write time, last access time, or security permissions in a file or directory in the specified Path of a FileSystemWatcher.

The Created event occurs when a file or directory in the specified Path of a FileSystemWatcher is created.

The Deleted event occurs when a file or directory in the specified Path of a FileSystemWatcher is deleted. For more information, see FileSystemWatcher.

The following example shows how to create a FileSystemWatcher to monitor file changes (creates, deletes, renames, changes) occurring on a disk drive. The example also shows how to properly receive error notifications.

using System;
using System.IO;

class Program
{
    static void Main(string[] args)
    {
        //  Create a FileSystemWatcher to monitor all files on drive C.
        FileSystemWatcher fsw = new FileSystemWatcher("C:\\");

        //  Watch for changes in LastAccess and LastWrite times, and
        //  the renaming of files or directories. 
        fsw.NotifyFilter = NotifyFilters.LastAccess | NotifyFilters.LastWrite
            | NotifyFilters.FileName |NotifyFilters.DirectoryName;

        //  Register a handler that gets called when a 
        //  file is created, changed, or deleted.
        fsw.Changed += new FileSystemEventHandler(OnChanged);

        fsw.Created += new FileSystemEventHandler(OnChanged);

        fsw.Deleted += new FileSystemEventHandler(OnChanged);

        //  Register a handler that gets called when a file is renamed.
        fsw.Renamed += new RenamedEventHandler(OnRenamed);

        //  Register a handler that gets called if the 
        //  FileSystemWatcher needs to report an error.
        fsw.Error += new ErrorEventHandler(OnError);

        //  Begin watching.
        fsw.EnableRaisingEvents = true;

        Console.WriteLine("Press \'Enter\' to quit the sample.");
        Console.ReadLine();


    }

    //  This method is called when a file is created, changed, or deleted.
    private static void OnChanged(object source, FileSystemEventArgs e)
    {
        //  Show that a file has been created, changed, or deleted.
        WatcherChangeTypes wct = e.ChangeType;
        Console.WriteLine("File {0} {1}", e.FullPath, wct.ToString());
    }

    //  This method is called when a file is renamed.
    private static void OnRenamed(object source, RenamedEventArgs e)
    {
        //  Show that a file has been renamed.
        WatcherChangeTypes wct = e.ChangeType;
        Console.WriteLine("File {0} {2} to {1}", e.OldFullPath, e.FullPath, wct.ToString());
    }

    //  This method is called when the FileSystemWatcher detects an error.
    private static void OnError(object source, ErrorEventArgs e)
    {
        //  Show that an error has been detected.
        Console.WriteLine("The FileSystemWatcher has detected an error");
        //  Give more information if the error is due to an internal buffer overflow.
        if (e.GetException().GetType() == typeof(InternalBufferOverflowException))
        {
            //  This can happen if Windows is reporting many file system events quickly 
            //  and internal buffer of the  FileSystemWatcher is not large enough to handle this
            //  rate of events. The InternalBufferOverflowException error informs the application
            //  that some of the file system events are being lost.
            Console.WriteLine(("The file system watcher experienced an internal buffer overflow: " + e.GetException().Message));
        }
    }

}

.NET Framework
Available since 1.1

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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