Graphics.DrawArc Method (Pen, RectangleF, Single, Single)

Draws an arc representing a portion of an ellipse specified by a RectangleF structure.

Namespace: System.Drawing
Assembly: System.Drawing (in system.drawing.dll)

public void DrawArc (
	Pen pen,
	RectangleF rect,
	float startAngle,
	float sweepAngle
public void DrawArc (
	Pen pen, 
	RectangleF rect, 
	float startAngle, 
	float sweepAngle
public function DrawArc (
	pen : Pen, 
	rect : RectangleF, 
	startAngle : float, 
	sweepAngle : float
Not applicable.



Pen that determines the color, width, and style of the arc.


RectangleF structure that defines the boundaries of the ellipse.


Angle in degrees measured clockwise from the x-axis to the starting point of the arc.


Angle in degrees measured clockwise from the startAngle parameter to ending point of the arc.

Exception typeCondition


pen is a null reference (Nothing in Visual Basic)

This method draws an arc that is a portion of the perimeter of an ellipse. The ellipse is defined by the boundaries of a rectangle. The arc is the portion of the perimeter of the ellipse between the startAngle parameter and the startAngle+ sweepAngle parameters.

The following code example is designed for use with Windows Forms, and it requires PaintEventArgse, which is a parameter of the Paint event handler. The code performs the following actions:

  • Creates a black pen.

  • Creates a rectangle to bound an ellipse.

  • Defines the start (45 degrees) and sweep (270 degrees) angles.

  • Draws the elliptical arc to the screen.

The result is a partial ellipse missing a segment between + and - 45 degrees of the x axis.

private void DrawArcRectangleF(PaintEventArgs e)
    // Create pen.
    Pen blackPen= new Pen(Color.Black, 3);
    // Create rectangle to bound ellipse.
    RectangleF rect = new RectangleF(0.0F, 0.0F, 100.0F, 200.0F);
    // Create start and sweep angles on ellipse.
    float startAngle =  45.0F;
    float sweepAngle = 270.0F;
    // Draw arc to screen.
    e.Graphics.DrawArc(blackPen, rect, startAngle, sweepAngle);

Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0