当下拉菜单值改变时，将下拉菜单当前值赋给文本框如何实现？

Question

<script language="javascript">
document.all["文本框的ID"].value = document.all["下拉框ID"].options[document.all["下拉框ID"].seletedIndex].value
</script>

Answer 1

<script language="javascript">
document.all["文本框的ID"].value = document.all["下拉框ID"].value
</script>

Answer 2

<select id="下拉" onchange="a()">....</select><script language="javascript">
function a()
{
document.all["文本框的ID"].value = document.all["下拉框ID"].value
}
</script>