.net 中关于timer使用的小问题，请指教

Timer t= new Timer();
t.Interval = 10000;
t.Tick += new EventHandler(t_Tick);
int x=3;
public void Page_Load(object sender, EventArgs e)
{
t.Interval=10000;
}
//在需要时激活Timer，t.Start();
public void t_Tick(object sender, EventArgs e)
{
if(x>0){
if(MessageBox.Show("OUT or Go on!",MessageBoxButtons.YesNo)==DialogResult.NO)
{
x--;
}
else{t.Stop();}}
}

Timer timer = new Timer();
timer.Interval = 10000;
timer.Tick += new EventHandler(timer_Tick);

void timer_Tick(object sender, EventArgs e)
{
MessageBox.Show("timeout");
timer.Stop();
}
private void button1_Click(object sender, EventArgs e)
{

if (DialogResult.No.Equals(MessageBox.Show("Hello", "", MessageBoxButtons.YesNo)))
{
timer.Start();
}
}