[.NET] How to implement rotate image in user control.

Introduction
Sometimes we need to rotate image in user control.
I override OnPaint method, and use Graphics.RotateTransform to rotate image.

Source Code

protected override void OnPaint(PaintEventArgs e)
{
    e.Graphics.SmoothingMode = SmoothingMode.Default;
    Rectangle rect=new Rectangle(0,0,this.Width,this.Height);
    PointF center=new PointF(rect.Width/2,rect.Height/2);

    float offsetX=0;
    float offsetY=0;
    offsetX = center.X - DoorWidth / 2;
    offsetY = center.Y - DoorHeight / 2;
    picRect = new RectangleF(offsetX, offsetY, DoorWidth, DoorHeight);
    PointF Pcenter=new PointF(picRect.X+picRect.Width/2,
        picRect.Y+picRect.Height/2);

    e.Graphics.TranslateTransform(Pcenter.X, Pcenter.Y);
    e.Graphics.RotateTransform(-m_i4Angle);
           
    e.Graphics.TranslateTransform(-Pcenter.X, -Pcenter.Y);
    if (m_bIsOpened)
    {
        int t_i4doorWidth = (DoorWidth - DoorOpenWidth) / 2;
        RectangleF picRect1 = new RectangleF(offsetX, offsetY, t_i4doorWidth, DoorHeight);
        e.Graphics.FillRectangle(new SolidBrush(m_OpenColor), picRect1);
        RectangleF picRect2 = new RectangleF(offsetX + DoorOpenWidth + t_i4doorWidth, offsetY, t_i4doorWidth, DoorHeight);
        e.Graphics.FillRectangle(new SolidBrush(m_OpenColor), picRect2);
    }
    else
    {
        e.Graphics.FillRectangle(new SolidBrush(m_CloseColor), picRect);
    }
    e.Graphics.ResetTransform();
}

Image