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Color::A Property

Gets the alpha component value of this Color structure.

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

public:
property unsigned char A {
	unsigned char get ();
}

Property Value

Type: System::Byte
The alpha component value of this Color.

The color of each pixel is represented as a 32-bit number: 8 bits each for alpha, red, green, and blue (ARGB). The alpha component specifies the transparency of the color: 0 is fully transparent, and 255 is fully opaque. Likewise, an A value of 255 represents an opaque color. An A value from 1 through 254 represents a semitransparent color. The color becomes more opaque as A approaches 255.

The following code example demonstrates the A, R, G, and B properties of a Color, and the Implicit member.

This example is designed to be used with a Windows Form. Paste the code into the form and call the ShowPropertiesOfSlateBlue method from the form's Paint event-handling method, passing e as PaintEventArgs.


void ShowPropertiesOfSlateBlue( PaintEventArgs^ e )
{
   Color slateBlue = Color::FromName( "SlateBlue" );
   Byte g = slateBlue.G;
   Byte b = slateBlue.B;
   Byte r = slateBlue.R;
   Byte a = slateBlue.A;
   array<Object^>^temp0 = {a,r,g,b};
   String^ text = String::Format( "Slate Blue has these ARGB values: Alpha:{0}, "
   "red:{1}, green: {2}, blue {3}", temp0 );
   e->Graphics->DrawString( text, gcnew System::Drawing::Font( this->Font,FontStyle::Italic ), gcnew SolidBrush( slateBlue ), RectangleF(PointF(0.0F,0.0F),this->Size) );
}


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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