Color.FromKnownColor(KnownColor) Metodo

public:
 static System::Drawing::Color FromKnownColor(System::Drawing::KnownColor color);

public static System.Drawing.Color FromKnownColor (System.Drawing.KnownColor color);

static member FromKnownColor : System.Drawing.KnownColor -> System.Drawing.Color

Public Shared Function FromKnownColor (color As KnownColor) As Color

Parametri

Restituisce

Oggetto Color creato con questo metodo.

Esempio

L'esempio di codice seguente è progettato per l'uso con Windows Forms e richiede PaintEventArgse, che è un parametro del Paint gestore eventi. Il codice esegue le azioni seguenti:

• Crea un'istanza di una Color struttura, redShade, da utilizzare per i confronti.

• Scorre gli elementi di KnownColor enumerazione per trovare tutti i colori noti con la stessa leggerezza di redShade. Le iterazioni vengono terminate quando vengono trovate 15 corrispondenze o il valore del contatore del ciclo è maggiore dell'ultimo KnownColor elemento.

• Durante ogni iterazione, salva l'elemento KnownColor , se corrisponde ai criteri, in una matrice.

• Usa un pennello per disegnare rettangoli.

Il primo rettangolo viene disegnato il colore rappresentato da redShade. Ognuno degli altri rettangoli viene dipinto un KnownColor oggetto che corrisponde alla leggerezza dell'oggetto redShade.

void KnownColorBrightnessExample1( PaintEventArgs^ e )
{
   Graphics^ g = e->Graphics;

   // Color structures. One is a variable used for temporary storage. The other
   // is a constant used for comparisons.
   Color someColor = Color::FromArgb( 0 );
   Color redShade = Color::FromArgb( 255, 200, 0, 100 );

   // Array to store KnownColor values that match the brightness of the
   // redShade color.
   array<KnownColor>^colorMatches = gcnew array<KnownColor>(15);

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

   // Iterate through the KnownColor enums until 15 matches are found.
   for ( KnownColor enumValue = (KnownColor)0; enumValue <= KnownColor::YellowGreen && count < 15; enumValue = enumValue + (KnownColor)1 )
   {
      someColor = Color::FromKnownColor( enumValue );
      if ( someColor.GetBrightness() == redShade.GetBrightness() )
               colorMatches[ count++ ] = enumValue;
   }

   // Display the redShade color and its argb value.
   SolidBrush^ myBrush1 = gcnew SolidBrush( redShade );
   System::Drawing::Font^ myFont = gcnew System::Drawing::Font( "Arial",12 );
   int x = 20;
   int y = 20;
   someColor = redShade;
   g->FillRectangle( myBrush1, x, y, 100, 30 );
   g->DrawString( someColor.ToString(), myFont, Brushes::Black, (float)x + 120, (float)y );
   
   // 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.
   for ( int i = 0; i < count; i++ )
   {
      y += 40;
      someColor = Color::FromKnownColor( colorMatches[ i ] );
      myBrush1->Color = someColor;
      g->FillRectangle( myBrush1, x, y, 100, 30 );
      g->DrawString( someColor.ToString(), myFont, Brushes::Black, (float)x + 120, (float)y );
   }
}

public void KnownColorBrightnessExample1(PaintEventArgs e)
{
    Graphics     g = e.Graphics;
             
    // Color structures. One is a variable used for temporary storage. The other
    // is a constant used for comparisons.
    Color   someColor = Color.FromArgb(0);
    Color   redShade = Color.FromArgb(255, 200, 0, 100);
             
    // Array to store KnownColor values that match the brightness of the
    // redShade color.
    KnownColor[]  colorMatches = new KnownColor[15];
     
    // Number of matches found.
    int  count = 0;   
          
    // Iterate through the KnownColor enums until 15 matches are found.
    for (KnownColor enumValue = 0;
        enumValue <= KnownColor.YellowGreen && count < 15; enumValue++)
    {
        someColor = Color.FromKnownColor(enumValue);
        if (someColor.GetBrightness() == redShade.GetBrightness())
            colorMatches[count++] = enumValue;
    }
             
    // Display the redShade color and its argb value.
    SolidBrush  myBrush1 = new SolidBrush(redShade);
    Font        myFont = new Font("Arial", 12);
    int         x = 20;
    int         y = 20;
    someColor = redShade;
    g.FillRectangle(myBrush1, x, y, 100, 30);
    g.DrawString(someColor.ToString(), myFont, Brushes.Black, x + 120, y);
             
    // 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.
    for (int i = 0; i < count; i++)
    {
        y += 40;
        someColor = Color.FromKnownColor(colorMatches[i]);
        myBrush1.Color = someColor;
        g.FillRectangle(myBrush1, x, y, 100, 30);
        g.DrawString(someColor.ToString(), myFont, Brushes.Black, x + 120, y);
    }
}

Public Sub KnownColorBrightnessExample1(ByVal e As PaintEventArgs)
    Dim g As Graphics = e.Graphics

    ' Color structures. One is used for temporary storage. The other
    ' is a constant used for comparisons.
    Dim someColor As Color = Color.FromArgb(0)
    Dim redShade As Color = Color.FromArgb(255, 200, 0, 100)

    ' Array to store KnownColor values that match the brightness of the
    ' redShade color.
    Dim colorMatches(15) As KnownColor

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

    ' iterate through the KnownColor enums until 15 matches are found.
    Dim enumValue As KnownColor
    For enumValue = 0 To KnownColor.YellowGreen
        someColor = Color.FromKnownColor(enumValue)
        If (someColor.GetBrightness()) = (redShade.GetBrightness()) Then
            colorMatches(count) = enumValue
            count += 1
            If count > 15 Then
                Exit For
            End If
        End If
    Next enumValue

    ' Display the redShade color and its argb value.
    Dim myBrush1 As New SolidBrush(redShade)
    Dim myFont As New Font("Arial", 12)
    Dim x As Integer = 20
    Dim y As Integer = 20
    someColor = redShade
    g.FillRectangle(myBrush1, x, y, 100, 30)
    g.DrawString(someColor.ToString(), myFont, Brushes.Black, _
    x + 120, y)

    ' Iterate through the matches that were found and display each
    ' color that corresponds with the enum value in the array.
    ' Display the name of the KnownColor.
    Dim i As Integer
    For i = 0 To count - 1
        y += 40
        someColor = Color.FromKnownColor(colorMatches(i))
        myBrush1.Color = someColor
        g.FillRectangle(myBrush1, x, y, 100, 30)
        g.DrawString(someColor.ToString(), myFont, Brushes.Black, _
        x + 120, y)
    Next i
End Sub

Commenti

Un colore predefinito è detto anche colore noto ed è rappresentato da un elemento dell'enumerazione KnownColor .

Si applica a