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Color.ToArgb Method

Definition

Gets the 32-bit ARGB value of this Color structure.

public:
 int ToArgb();
public int ToArgb ();
member this.ToArgb : unit -> int
Public Function ToArgb () As Integer

Returns

The 32-bit ARGB value of this Color.

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:

  • Iterates through the KnownColor enumeration elements to find all known colors that have a non-zero green component and a zero-value red component, and that are not system colors.

  • During each iteration, saves the KnownColor element - if it matches the criteria - in an array.

  • Uses a brush to paint rectangles.

Each of the rectangles is painted a KnownColor that matches the criteria stated in the first bullet. The name of the KnownColor and its component values are also displayed.

This example displays certain known colors, the names of the colors, and their four component values. The ToArgb method is used as a preliminary step to display the component values.

void ToArgbToStringExample1( PaintEventArgs^ e )
{
   Graphics^ g = e->Graphics;

   // Color structure used for temporary storage.
   Color someColor = Color::FromArgb( 0 );

   // Array to store KnownColor values that match the criteria.
   array<KnownColor>^colorMatches = gcnew array<KnownColor>(167);

   // Number of matches found.
   int count = 0;

   // Iterate through the KnownColor enums to find all corresponding colors
   // that have a nonzero green component and zero-value red component and
   // that are not system colors.
   for ( KnownColor enumValue = (KnownColor)0; enumValue <= KnownColor::YellowGreen; enumValue = enumValue + (KnownColor)1 )
   {
      someColor = Color::FromKnownColor( enumValue );
      if ( someColor.G != 0 && someColor.R == 0 &&  !someColor.IsSystemColor )
               colorMatches[ count++ ] = enumValue;
   }
   SolidBrush^ myBrush1 = gcnew SolidBrush( someColor );
   System::Drawing::Font^ myFont = gcnew System::Drawing::Font( "Arial",9 );
   int x = 40;
   int y = 40;

   // Iterate through the matches that were found and display each color that
   // corresponds with the enum value in the array. also display the name of
   // the KnownColor and the ARGB components.
   for ( int i = 0; i < count; i++ )
   {
      // Display the color.
      someColor = Color::FromKnownColor( colorMatches[ i ] );
      myBrush1->Color = someColor;
      g->FillRectangle( myBrush1, x, y, 50, 30 );

      // Display KnownColor name and the four component values. To display the
      // component values:  Use the ToArgb method to get the 32-bit ARGB value
      // of someColor, which was created from a KnownColor. Then create a
      // Color structure from the 32-bit ARGB value and set someColor equal to
      // this new Color structure. Then use the ToString method to convert it to
      // a string.
      g->DrawString( someColor.ToString(), myFont, Brushes::Black, (float)x + 55, (float)y );
      someColor = Color::FromArgb( someColor.ToArgb() );
      g->DrawString( someColor.ToString(), myFont, Brushes::Black, (float)x + 55, (float)y + 15 );
      y += 40;
   }
}
      public void ToArgbToStringExample1(PaintEventArgs e)
      {
          Graphics     g = e.Graphics;
                   
          // Color structure used for temporary storage.
          Color   someColor = Color.FromArgb(0);
                   
          // Array to store KnownColor values that match the criteria.
          KnownColor[]  colorMatches = new KnownColor[167];
          
          // Number of matches found.
          int  count = 0; 

          // Iterate through the KnownColor enums to find all corresponding colors
          // that have a nonzero green component and zero-value red component and
          // that are not system colors.
          for (KnownColor enumValue = 0;
              enumValue <= KnownColor.YellowGreen; enumValue++)
          {
              someColor = Color.FromKnownColor(enumValue);
              if (someColor.G != 0 && someColor.R == 0 && !someColor.IsSystemColor)
                  colorMatches[count++] = enumValue;
          }
          SolidBrush  myBrush1 = new SolidBrush(someColor);
          Font        myFont = new Font("Arial", 9);
          int         x = 40;
          int         y = 40;
                   
          // Iterate through the matches that were found and display each color that
          // corresponds with the enum value in the array. also display the name of
          // the KnownColor and the ARGB components.
          for (int i = 0; i < count; i++)
          {
                   
              // Display the color.
              someColor = Color.FromKnownColor(colorMatches[i]);
              myBrush1.Color = someColor;
              g.FillRectangle(myBrush1, x, y, 50, 30);
                   
              // Display KnownColor name and the four component values. To display the
              // component values:  Use the ToArgb method to get the 32-bit ARGB value
              // of someColor, which was created from a KnownColor. Then create a
              // Color structure from the 32-bit ARGB value and set someColor equal to
              // this new Color structure. Then use the ToString method to convert it to
              // a string.
              g.DrawString(someColor.ToString(), myFont, Brushes.Black, x + 55, y);
              someColor = Color.FromArgb(someColor.ToArgb());
              g.DrawString(someColor.ToString(), myFont, Brushes.Black, x + 55, y + 15);
              y += 40;
          }
      }
Public Sub ToArgbToStringExample1(ByVal e As PaintEventArgs)
    Dim g As Graphics = e.Graphics

    ' Color structure used for temporary storage.
    Dim someColor As Color = Color.FromArgb(0)

    ' Array to store KnownColor values that match the criteria.
    Dim colorMatches(167) As KnownColor

    ' Number of matches found.
    Dim count As Integer = 0

    ' Iterate through KnownColor enums to find all corresponding colors
    ' that have a non-zero green component and zero-valued red
    ' component and that are not system colors.
    Dim enumValue As KnownColor
    For enumValue = 0 To KnownColor.YellowGreen
        someColor = Color.FromKnownColor(enumValue)
        If someColor.G <> 0 And someColor.R = 0 And _
        Not someColor.IsSystemColor Then
            colorMatches(count) = enumValue
            count += 1
        End If
    Next enumValue
    Dim myBrush1 As New SolidBrush(someColor)
    Dim myFont As New Font("Arial", 9)
    Dim x As Integer = 40
    Dim y As Integer = 40

    ' Iterate through the matches found and display each color that
    ' corresponds with the enum value in the array. Also display the
    ' name of the KnownColor and the ARGB components.
    Dim i As Integer
    For i = 0 To count - 1

        ' Display the color.
        someColor = Color.FromKnownColor(colorMatches(i))
        myBrush1.Color = someColor
        g.FillRectangle(myBrush1, x, y, 50, 30)

        ' Display KnownColor name and four component values. To display
        ' component values:  Use the ToArgb method to get the 32-bit
        ' ARGB value of someColor (created from a KnownColor). Create
        ' a Color structure from the 32-bit ARGB value and set someColor
        ' equal to this new Color structure. Then use the ToString method
        ' to convert it to a string.
        g.DrawString(someColor.ToString(), myFont, Brushes.Black, _
        x + 55, y)
        someColor = Color.FromArgb(someColor.ToArgb())
        g.DrawString(someColor.ToString(), myFont, Brushes.Black, _
        x + 55, y + 15)
        y += 40
    Next i
End Sub

Remarks

The byte-ordering of the 32-bit ARGB value is AARRGGBB. The most significant byte (MSB), represented by AA, is the alpha component value. The second, third, and fourth bytes, represented by RR, GG, and BB, respectively, are the color components red, green, and blue, respectively

Applies to