JavaScript实现下拉菜单对文本框赋值的小功能

<script language="javaScript">
  function changeValue() {
    testForm.t1.value = testForm.s1.value;
  }
</script>
<form name="testForm" action="">
  <select name="s1" onChange="changeValue()">
    <option value="ddddd">1111</option>
    <option value="bbbbbb">2222</option>
  </select>
  <input type="text" name="t1">
</form>

感谢July~~ ^_^