Color.FromKnownColor(KnownColor) 方法
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
從指定的預先定義色彩建立 Color 結構。
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
參數
- color
- KnownColor
KnownColor 列舉的 元素。
傳回
這個方法所建立的 Color。
範例
下列程式代碼範例是專為搭配 Windows Forms 使用而設計,而且需要 PaintEventArgse
,這是 Paint 事件處理程式的參數。 程式代碼會執行下列動作:
建立要用於比較之 Color 結構的實例,
redShade
。逐一查看 KnownColor 列舉元素,以尋找與
redShade
相同的已知色彩。 當找到 15 個相符項目或循環計數器的值大於最後一個 KnownColor 元素時,反覆運算就會終止。在每個反覆項目期間,會將 KnownColor 項目儲存在陣列中,如果它符合準則則為 。
使用筆刷繪製矩形。
第一個矩形會繪製 redShade
所代表的色彩。 每個其他矩形都會繪製符合 redShade
光線的 KnownColor。
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
備註
預先定義的色彩也稱為已知色彩,並以 KnownColor 列舉的 元素表示。