Form.Close Method

Closes the form.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in

Public Sub Close
Dim instance As Form

public void Close ()
public function Close ()

Exception typeCondition


The form was closed while a handle was being created.


You cannot call this method from the Activated event when WindowState is set to Maximized.

When a form is closed, all resources created within the object are closed and the form is disposed. You can prevent the closing of a form at run time by handling the Closing event and setting the Cancel property of the CancelEventArgs passed as a parameter to your event handler. If the form you are closing is the startup form of your application, your application ends.

The one condition when a form is not disposed on Close is when it is part of a multiple-document interface (MDI) application, and the form is not visible. In this case, you will need to call Dispose manually to mark all of the form's controls for garbage collection.


When the Close method is called on a Form displayed as a modeless window, you cannot call the Show method to make the form visible, because the form's resources have already been released. To hide a form and then make it visible, use the Control.Hide method.

Caution noteCaution

Do not call M:System.Windows.Forms.Form.Close from within an event handler for either the Load or Activated events. Both conditions can cause memory leaks. To test whether you should close a form shortly after it has loaded, use the Idle event instead.

Caution noteCaution

The Form.Closed and Form.Closing events are not raised when the Application.Exit method is called to exit your application. If you have validation code in either of these events that must be executed, you should call the Form.Close method for each open form individually before calling the Exit method.

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0

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