# Color.ToArgb 方法

## 定义

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

#### 返回

Color 的 32 位 ARGB 值。The 32-bit ARGB value of this Color.

## 示例

• 循环访问 KnownColor 枚举元素，查找具有非零绿色分量和零值红色分量，并且不是系统颜色的所有已知颜色。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.

• 在每次迭代过程中，会保存 KnownColor 元素（如果它匹配数组中的条件）。During each iteration, saves the KnownColor element - if it matches the criteria - in an array.

• 使用画笔绘制矩形。Uses a brush to paint rectangles.

``````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
``````

## 注解

32位 ARGB 值的字节顺序为 AARRGGBB。The byte-ordering of the 32-bit ARGB value is AARRGGBB. 最有效的字节（MSB）由 AA 表示，它是 alpha 分量值。The most significant byte (MSB), represented by AA, is the alpha component value. 第二个、第三个和第四个字节分别由 RR、GG 和 BB 表示，分别为红色、绿色和蓝色的颜色部分The second, third, and fourth bytes, represented by RR, GG, and BB, respectively, are the color components red, green, and blue, respectively