Color.ToString Metodo

Definizione

Spazio dei nomi:

System.Drawing

Assembly:

System.Drawing.Primitives.dll

Origine:

Color.cs

Converte questa struttura Color in una stringa leggibile.

public:
 override System::String ^ ToString();

public override string ToString ();

override this.ToString : unit -> string

Public Overrides Function ToString () As String

Restituisce

String

Stringa che rappresenta il nome di questa struttura Color, se la struttura Color viene creata da un colore predefinito tramite il metodo FromName(String) oppure FromKnownColor(KnownColor); in caso contrario, stringa formata dai nomi dei componenti ARGB e dai relativi valori.

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:

• Esegue l'iterazione KnownColor degli elementi di enumerazione per trovare tutti i colori noti che hanno un componente verde diverso da zero e un componente rosso con valore zero e che non sono colori di sistema.

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

• Usa un pennello per disegnare rettangoli. Ognuno dei rettangoli è dipinto che KnownColor corrisponde ai criteri indicati nel primo passaggio. Viene visualizzato anche il nome del componente e i KnownColor relativi valori di componente.

In questo esempio vengono visualizzati determinati colori noti e usati ToString per visualizzare i nomi dei colori e i relativi quattro valori dei componenti.

void ToArgbToStringExample2( 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 ToArgbToStringExample2(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 ToArgbToStringExample2(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

Commenti

Un colore predefinito viene chiamato anche un colore noto ed è rappresentato da un elemento dell'enumerazione KnownColor . Quando il metodo viene applicato a una struttura creata usando il ToStringFromArgb metodo, restituisce una Color stringa costituita dai nomi dei componenti ARGB e dai relativi valori, ToString anche se il valore ARGB corrisponde al valore ARGB di un colore predefinito.