Timer İnterval Örneği

int i = 0;
        public Form1()
        {
            InitializeComponent();
        }

        private void timer1_Tick(object sender, EventArgs e)
        {
            i--;
            label1.Text = i.ToString();
            if (i == 0)
            {

                timer1.Enabled = false;
                MessageBox.Show("Süreniz doldu...");

            }

        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void button1_Click(object sender, EventArgs e)
        {
            timer1.Enabled = true;
            timer1.Interval = Convert.ToInt32(comboBox1.Text);
            i = Convert.ToInt32(textBox1.Text);
        }