Color.GetHue Metodo

Definizione

Spazio dei nomi:

System.Drawing

Assembly:

System.Drawing.Primitives.dll

Origine:

Color.cs

Ottiene il valore della tonalità HSL (Hue-saturation-light) in gradi per questa struttura Color.

public:
 float GetHue();

public float GetHue ();

member this.GetHue : unit -> single

Public Function GetHue () As Single

Restituisce

Single

Tonalità, in gradi, di questo Color. La tonalità viene misurata in gradi, compreso tra 0,0 e 360,0, nello spazio dei colori HSL.

Esempio

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

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

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

• 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 disegnato un KnownColor che corrisponde alla tonalità del redShade.

void GetHueExample( 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 hue 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.GetHue() == redShade.GetHue() )
               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 GetHueExample(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 hue 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.GetHue() == redShade.GetHue())
            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 GetHueExample(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 for KnownColor values that match the hue of 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.GetHue()) = (redShade.GetHue()) 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. Also
    ' 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