Color.FromArgb Method (Int32, Int32, Int32) (System.Drawing)

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.NET Framework Class Library

Color.FromArgb Method (Int32, Int32, Int32)

Creates a Color structure from the specified 8-bit color values (red, green, and blue). The alpha value is implicitly 255 (fully opaque). Although this method allows a 32-bit value to be passed for each color component, the value of each component is limited to 8 bits.

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

Syntax

Visual Basic

Public Shared Function FromArgb ( _
	red As Integer, _
	green As Integer, _
	blue As Integer _
) As Color

public static Color FromArgb(
	int red,
	int green,
	int blue
)

Visual C++

public:
static Color FromArgb(
	int red, 
	int green, 
	int blue
)

static member FromArgb : 
        red:int * 
        green:int * 
        blue:int -> Color

Parameters

red: Type: System.Int32
The red component value for the new Color. Valid values are 0 through 255.

green: Type: System.Int32
The green component value for the new Color. Valid values are 0 through 255.

blue: Type: System.Int32
The blue component value for the new Color. Valid values are 0 through 255.

Return Value

Type: System.Drawing.Color
The Color that this method creates.

Exceptions

Exception	Condition
ArgumentException	red, green, or blue is less than 0 or greater than 255.

Examples

The following code example is designed for use with Windows Forms, and it requires PaintEventArgs e, which is a parameter of the Paint event handler. The code performs the following actions:

Creates Color structures from the three color component values (red, green, blue). Three Color structures are created, one for each primary color.
Iterates through a range of alpha values, changing the alpha value of a color.
During each iteration, sets the color of a brush to the modified color and paints a rectangle to show the color.
Repeats steps 2 and 3 for each primary color.

The alpha value is never fully opaque and the rectangles overlap so you get color-combination effects.

Visual Basic


Public Sub FromArgb2(ByVal e As PaintEventArgs)
    Dim g As Graphics = e.Graphics

    ' Opaque colors (alpha value defaults to 255 -- max value).
    Dim red As Color = Color.FromArgb(255, 0, 0)
    Dim green As Color = Color.FromArgb(0, 255, 0)
    Dim blue As Color = Color.FromArgb(0, 0, 255)

    ' Solid brush initialized to red.
    Dim myBrush As New SolidBrush(red)
    Dim alpha As Integer

    ' x coordinate of first red rectangle.
    Dim x As Integer = 50

    ' y coordinate of first red rectangle.
    Dim y As Integer = 50

    ' Fill rectangles with red, varying the alpha value from 25 to 250.
    For alpha = 25 To 250 Step 25
        myBrush.Color = Color.FromArgb(alpha, red)
        g.FillRectangle(myBrush, x, y, 50, 100)
        g.FillRectangle(myBrush, x, y + 250, 50, 50)
        x += 50
    Next alpha

    ' x coordinate of first green rectangle.
    x = 50

    ' y coordinate of first green rectangle.
    y += 50


    ' Fill rectangles with green, varying alpha value from 25 to 250.
    For alpha = 25 To 250 Step 25
        myBrush.Color = Color.FromArgb(alpha, green)
        g.FillRectangle(myBrush, x, y, 50, 150)
        x += 50
    Next alpha

    ' x coordinate of first blue rectangle.
    x = 50

    ' y coordinate of first blue rectangle.
    y += 100

    ' Fill rectangles with blue, varying alpha value from 25 to 250.
    For alpha = 25 To 250 Step 25
        myBrush.Color = Color.FromArgb(alpha, blue)
        g.FillRectangle(myBrush, x, y, 50, 150)
        x += 50
    Next alpha
End Sub


public void FromArgb2(PaintEventArgs e)
{
    Graphics     g = e.Graphics;

    // Opaque colors (alpha value defaults to 255 -- max value).
    Color red = Color.FromArgb(255, 0, 0);
    Color green = Color.FromArgb(0, 255, 0);
    Color blue = Color.FromArgb(0, 0, 255);

    // Solid brush initialized to red.
    SolidBrush  myBrush = new SolidBrush(red);
    int alpha;

    // x coordinate of first red rectangle
    int x = 50;         

    // y coordinate of first red rectangle
    int y = 50;         

    // Fill rectangles with red, varying the alpha value from 25 to 250.
    for (alpha = 25; alpha <= 250; alpha += 25)
    {
        myBrush.Color = Color.FromArgb(alpha, red);
        g.FillRectangle(myBrush, x, y, 50, 100);
        g.FillRectangle(myBrush, x, y + 250, 50, 50);
        x += 50;
    }
    // x coordinate of first green rectangle.
    x = 50;             

    // y coordinate of first green rectangle.
    y += 50;            

    // Fill rectangles with green, varying the alpha value from 25 to 250.
    for (alpha = 25; alpha <= 250; alpha += 25)
    {
        myBrush.Color = Color.FromArgb(alpha, green);
        g.FillRectangle(myBrush, x, y, 50, 150);
        x += 50;
    }
    // x coordinate of first blue rectangle.
    x = 50;             

    // y coordinate of first blue rectangle.
    y += 100;           

    // Fill rectangles with blue, varying the alpha value from 25 to 250.
    for (alpha = 25; alpha <= 250; alpha += 25)
    {
        myBrush.Color = Color.FromArgb(alpha, blue);
        g.FillRectangle(myBrush, x, y, 50, 150);
        x += 50;
    }
}

Visual C++


void FromArgb2( PaintEventArgs^ e )
{
   Graphics^ g = e->Graphics;

   // Opaque colors (alpha value defaults to 255 -- max value).
   Color red = Color::FromArgb( 255, 0, 0 );
   Color green = Color::FromArgb( 0, 255, 0 );
   Color blue = Color::FromArgb( 0, 0, 255 );

   // Solid brush initialized to red.
   SolidBrush^ myBrush = gcnew SolidBrush( red );
   int alpha;

   // x coordinate of first red rectangle
   int x = 50;

   // y coordinate of first red rectangle
   int y = 50;

   // Fill rectangles with red, varying the alpha value from 25 to 250.
   for ( alpha = 25; alpha <= 250; alpha += 25 )
   {
      myBrush->Color = Color::FromArgb( alpha, red );
      g->FillRectangle( myBrush, x, y, 50, 100 );
      g->FillRectangle( myBrush, x, y + 250, 50, 50 );
      x += 50;
   }
   x = 50;

   // y coordinate of first green rectangle.
   y += 50;

   // Fill rectangles with green, varying the alpha value from 25 to 250.
   for ( alpha = 25; alpha <= 250; alpha += 25 )
   {
      myBrush->Color = Color::FromArgb( alpha, green );
      g->FillRectangle( myBrush, x, y, 50, 150 );
      x += 50;
   }
   x = 50;

   // y coordinate of first blue rectangle.
   y += 100;

   // Fill rectangles with blue, varying the alpha value from 25 to 250.
   for ( alpha = 25; alpha <= 250; alpha += 25 )
   {
      myBrush->Color = Color::FromArgb( alpha, blue );
      g->FillRectangle( myBrush, x, y, 50, 150 );
      x += 50;
   }
}

Version Information

.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

Platforms

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.

Reference

Color Structure

FromArgb Overload

System.Drawing Namespace