修改文本域的值：

	document.getElementById("myText").value = "Johnny Bravo";

获取文本域的值:

	var x = document.getElementById("myText").value;

x 输出结果为:

Mickey

表单验证:

var at = document.getElementById("email").value.indexOf("@");

var age = document.getElementById("age").value;

var fname = document.getElementById("fname").value;

submitOK = "true";

if (fname.length>10) {

    alert("姓名不能超过 10 个字符");

    submitOK = "false";

} 

if (isNaN(age)||age<1||age>100) {

    alert("年龄范围为 1 到 100");

    submitOK = "false";

}

if (at==-1) {

    alert("不合法的 e-mail!");

    submitOK = "false";

}

if (submitOK=="false") {

    return false;

}

表单的下拉列表:

	var mylist = document.getElementById("myList");
document.getElementById("favorite").value = mylist.options[mylist.selectedIndex].text;

另一个下拉列表:

	var no = document.getElementById("no");
var option = no.options[no.selectedIndex].text;

	var txt = document.getElementById("result").value;
txt = txt + option;

	document.getElementById("result").value = txt;