C#怎麽用Timer做壹個30秒倒計時小程序

{

int count = 30;

public Form1()

{

InitializeComponent();

textBox1.Text = count.ToString();

timer1.Start();

}

private void timer1_Tick(object sender, EventArgs e)

{

if (--count == 0)

count = 30;

textBox1.Text = count.ToString();

}

}