C#

protected override void OnPaint(PaintEventArgs e)
        {
            

            if (machineStatusON)
            {




                for (int i = 0; i < ECGArray.Length; i++)
                {


                    if (x > this.Width) x = 0;
                    x += 1;
                    px = x;
                    p = 60 - (ECGArray[i] / 3 + 50);
                    //e.Graphics.DrawLine(yelgpen, px, pp, x, p);
                    e.Graphics.DrawLine(yelgpen, px, pp + 30, x, p + 30);

                    e.Graphics.DrawLine(blackpen, x + 1, 0, x + 1, this.Height - 1);


                    pp = p;
                    pq = q;
                    pr = r;

                }
            }
        }

/////server

//Read Message 1
string string1FromClient = strReader.ReadLine();

//Reply Message 1
strWriter.WriteLine("client sent: "+ string1FromClient);
strWriter.Flush();

//Read Message 2  (if client doesn’t send this, server throws an exception error)
string string2FromClient = strReader.ReadLine();

/////Client

//send Message 1 (send it every minute)
strWriter.WriteLine("message");
strWriter.Flush();

//read reply to message 1
string stringFromServer = strReader.ReadLine();

//send Message 2  (apart from the first message, send it sometimes on user demand) 
strWriter.WriteLine("message");
strWriter.Flush();