private void test()
        {
            string[] arr = new string[4] { "啊", "饿", "一", "他" };
            Random ra = new Random();
            int num = 4;
            int chooes = ra.Next(num);
            MessageBox.Show(arr[chooes].ToString());
        }
        private void button1_Click(object sender, EventArgs e)
        {
            test();
        }