GraphicsPath.AddArc Method (Rectangle, Single, Single)
Appends an elliptical arc to the current figure.
Assembly: System.Drawing (in System.Drawing.dll)
Parameters
 rect

Type:
System.Drawing.Rectangle
A Rectangle that represents the rectangular bounds of the ellipse from which the arc is taken.
 startAngle

Type:
System.Single
The starting angle of the arc, measured in degrees clockwise from the xaxis.
 sweepAngle

Type:
System.Single
The angle between startAngle and the end of the arc.
If there are previous lines or curves in the figure, a line is added to connect the endpoint of the previous segment to the beginning of the arc.
The arc is traced along the perimeter of the ellipse bounded by the specified rectangle. The starting point of the arc is determined by measuring clockwise from the xaxis of the ellipse (at the 0degree angle) by the number of degrees in the start angle. The endpoint is similarly located by measuring clockwise from the starting point by the number of degrees in the sweep angle. If the sweep angle is greater than 360 degrees or less than 360 degrees, the arc is swept by exactly 360 degrees or 360 degrees, respectively.
The following code example is designed for use with Windows Forms, and it requires PaintEventArgse, an OnPaint event object. The code performs the following actions:
Creates a rectangle, from which the arc is defined.
Creates a path, myPath.
Defines a 180degree elliptical arc that sweeps from 0 degrees to 180 degrees and appends it to a path.
Draws the path to screen.
Available since 1.1