stop flickering
//How to stop flickering
//This answer is same for PictureBox, Form, Panel and etc.
//First, add this library.
using System.Reflection;
//change "MyPanel" with your panel name.
typeof(Panel).InvokeMember("DoubleBuffered", BindingFlags.SetProperty| BindingFlags.Instance | BindingFlags.NonPublic, null, MyPanel , new object[] { true });