How to add handler to multiple dyanamically created buttons in C#

You can add handler to dynamically created a button ,but might be confused with multiple buttons that is created dynamically .

Here is the given code to understand.

for (int i = 0; i < 10; ++i)
            {
                Button btn = new Button();
                btn.Text = "btn" + i.ToString() + "";
                btn.ID = "btn_" + i.ToString() + "";
                btn.Click += new EventHandler(btnSave_Click1);
                btn.CommandName = i.ToString();
                btn.CommandArgument = i.ToString();
                div1.Controls.Add(btn);
            }
            
          
        }
        protected void btnSave_Click1(object sender, EventArgs e)
        {
            Button btn = (Button)sender;
          
          switch (int.Parse(btn.CommandName))
          {
                case 0:
                    DoWhatever(btn.CommandArgument.ToString());
                    break;
                case 1:
                    DoSomethingElse(btn.CommandArgument.ToString());
                    break;
           }

        }
        private void DoWhatever(string args)
        {
            string ss = string.Empty;
        }
        private void DoSomethingElse(string args)
        {
        }