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c# - What's the best way to keep log for events of windows form application?
private AddUser(User id)
    {
        if(id != null)
        {
            MessageBox.Show("Item Updated");
            string sqlAddUser = "INSERT INTO 'DATABASE.USER' VALUES (Item.ID, Item.Name, Item.Address)";
            if(db.SqlNonQuery(sqlAddUser) //If successful
            {
                ///To DO : Add system log into database
                ///Ex. string sqlLog = DateTime.Now + User.ID + " added Item ID " + item.ID;
            }
            else
            {
                MessageBox.Show("Error");
            }
        }
    }