Form.ResizeBegin Event

Note: This event is new in the .NET Framework version 2.0.

Occurs when a form enters resizing mode.

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

public event EventHandler ResizeBegin
/** @event */
public void add_ResizeBegin (EventHandler value)

/** @event */
public void remove_ResizeBegin (EventHandler value)

JScript supports the use of events, but not the declaration of new ones.

The ResizeBegin event is raised when the user begins to resize a form, typically by clicking and dragging one of the borders or the sizing grip located on the lower-right corner of the form. This action puts the form into a modal sizing loop until the resize operation is completed. Typically, the following set of events occurs during a resize operation:

  1. A single ResizeBegin event occurs as the form enters resizing mode.

  2. Zero or more pairs of Resize and SizeChanged events occur as the form's Size is modified.

  3. A single ResizeEnd event occurs as the form exits resizing mode.


Just clicking without dragging on a border or resizing grip will generate the ResizeBegin and ResizeEnd events without any intermediate Resize and SizeChanged event pairs.

The ResizeBegin and ResizeEnd pair of events is also raised when the user moves the form, typically by clicking and dragging on the caption bar. These events are not generated by programmatic manipulation of the form, for example by changing the Size or Location properties.

For more information about handling events, see Consuming Events.

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