Many ActiveX controls use a special type named OLE_COLOR to represent colors. Methods and properties that accept a color specification of OLE_COLOR type expect that specification to be a number representing an RGB color value. An RGB color value specifies the relative intensity of red, green, and blue in a specific color to be displayed.
The intensities of red, green, and blue are each represented by a number between 0 and 255. These three numbers are combined to form a single OLE_COLOR.
OLE_COLOR is treated internally as a 32-bit integer. The least significant byte is the value representing the red component of the color. The second least significant byte represents the green component, and the third least significant byte represents the blue component.
The following table lists some standard colors and the red, green, and blue values they include:
| Color | Red Value | Green Value | Blue Value |
|---|---|---|---|
| Black | 0 | 0 | 0 |
| Blue | 0 | 0 | 255 |
| Green | 0 | 255 | 0 |
| Cyan | 0 | 255 | 255 |
| Red | 255 | 0 | 0 |
| Magenta | 255 | 0 | 255 |
| Yellow | 255 | 255 | 0 |
| White | 255 | 255 | 255 |
To construct an OLE_COLOR from the red, green, and blue numbers, use the following formula:
OLE_COLOR = red + (green * 256) + (blue * 65536)
or using hexadecimal literals:
OLE_COLOR = red + (green * x#100) + (blue * x#10000)
As a convenience, eight standard colors have been defined in ACTIVEX.DEF.
*Standard OLE_COLOR Values: 78 OLE-BLACK VALUE X#000000 78 OLE-BLUE VALUE X#0000FF 78 OLE-GREEN VALUE X#00FF00 78 OLE-CYAN VALUE X#00FFFF 78 OLE-RED VALUE X#FF0000 78 OLE-MAGENTA VALUE X#FF00FF 78 OLE-YELLOW VALUE X#FFFF00 78 OLE-WHITE VALUE X#FFFFFF