Gets or sets the color that will represent transparent areas of the form.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
When the property is assigned a Color, the areas of the form that have the same BackColor will be displayed transparently. Any mouse actions, such as the click of the mouse, that are performed on the transparent areas of the form will be transferred to the windows below the transparent area. For example, if the client region of a form is made transparent, clicking the mouse on that area would send the event notification of the click to any window that is below it. If the color assigned to the property is the same as any controls on the form, they also will be displayed transparently. For example, if you have a Button control on a form that has its property set to SystemColors.Control, the control will be displayed transparently unless the BackColor property of the Button control is changed to a different color.
This property is not supported when RightToLeftLayout is true.
Windows 2000, Windows Server 2003, Windows XP Home Edition, Windows XP Professional x64 Edition, Windows Server 2003 Platform Note: Transparent windows and regions are only supported starting with Windows 2000.
The following code example creates a window that has a transparent client region regardless of background color of the form. This example requires that the example method is defined within a form class.
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.