VOID Example_DrawPie4(HDC hdc)
{
Graphics graphics(hdc);
// Create a Pen object.
Pen blackPen(Color(255, 0, 0, 0), 3);
// Define the pie.
REAL x = 0.0f;
REAL y = 0.0f;
REAL width = 200.0f;
REAL height = 100.0f;
REAL startAngle = 0.0f; //起始角度
REAL sweepAngle = 45.0f; //这里不就是控制角度.
// Draw the pie.
graphics.DrawPie(&blackPen, x, y, width, height, startAngle, sweepAngle);
}