SOURCE

function timedText()
{
var t1=setTimeout("document.getElementById('txt').value='2 seconds!'",2000)
var t2=setTimeout("document.getElementById('txt').value='4 seconds!'",4000)
var t3=setTimeout("document.getElementById('txt').value='6 seconds!'",6000)
}

<form> 
  <input type="button" value="显示计时的文本！" onclick="timedText()"> 
  <input type="text" id="txt"> 
 </form> 
 <p>在按钮上面点击。输入框会显示出已经流逝的 2、4、6 秒钟。</p>