C#

// distance = Pythagorean 
Func<Point, Point, double> distanceToken = new Func<Point, Point, double>((p1, p2) => { return ((p1.X - p2.X) * (p1.X - p2.X)) + ((p1.Y - p2.Y) * (p1.Y - p2.Y)); });

            Point TopLeft = new Point() { X = 0, Y = 0 };  // or however you want to define it. 
            Point BottomRight = new Point() { X = 100, Y = 100 };  // or however you want to define it.


//assuming that you can measure the desired distance with 1 point ( nearest top left and farthest top left ( which is bottom right )
            var t = (from pt in points
                    select new { p=pt, d= distanceToken (TopLeft, pt) }).OrderBy(a=>a.d);

            Console.WriteLine("nearest topleft:" + t.First().ToString());
            Console.WriteLine("farthest topleft:" + t.Last().ToString());

//othewise using two points 
            var t = (from pt in points
                     select new { p = pt, DistToA = distanceToken (TopLeft, pt), DistToB = distanceToken(BottomRight, pt) });

cechode wrote:

Math.Sqrt(Math.Pow(Math.Abs(p1.X - p2.X), 2) + Math.Pow(Math.Abs(p1.Y - p2.Y), 2))

Func distanceSquared = new Func((p1, p2) => 
    { 
        return (p1.X - p2.X) * (p1.X - p2.X) + (p1.Y - p2.Y) * (p1.Y - p2.Y); 
    });

private Rectangle myRect = new Rectangle(0, 0, 40, 30);
private void myPanel_Paint(object sender, PaintEventArgs e)
    {
    Graphics g = e.Graphics;
    g.DrawRectangle(Pens.Azure, myRect);
    }

5883 wrote:

Anyone knows a working example in c# ?

jrahma wrote:

How?

void Post(MethodInvoker methodInvoker)
{
    Post(new SendOrPostCallback((object useless) => { methodInvoker(); }));
}

harold aptroot wrote:

if this was what you meant you wouldn't have asked

void Post(MethodInvoker methodInvoker)
{
    Post(delegate (object useless) { methodInvoker(); });
}

class HolderThingy
{
    public MethodInvoker methodInvoker;
    
    public void Invoke(object useless)
    {
        methodInvoker();
    }
}

void Post(MethodInvoker methodInvoker)
{
    HolderThingy holder = new HolderThingy();
    holder.methodInvoker = methodInvoker;
    Post(new SendOrPostCallback(holder.Invoke));
}

object useless