随笔 - 11  文章 - 0  评论 - 0  阅读 - 14934

select

 

jsp 页面

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ page import="java.util.Date" %>
<%@page import="java.text.SimpleDateFormat" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>

<%                      //java 代码
Date d= new Date();
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String str = df.format(d);
%>
<%=str %>                  //显示出来

<select size=1>
<option value="1" >one</option>
<option value="2" >two</option>
<option value="3" selected>three</option>      //selected 表示此项被选为默认 
<option value="4" >four</option>
</select>

<%-- <jsp:forward page="wrong.jsp"/> --%>     //请求转发

</body>
</html>

 

select 的小技巧

1.动态创建select

function createSelect(){

var mySelect = document.createElement("select"); 
mySelect.id = "mySelect"; 
document.body.appendChild(mySelect);
}

2.添加选项option

function addOption(){

//根据id查找对象,
var obj=document.getElementById('mySelect');

//添加一个选项
obj.add(new Option("文本","值")); 
}

3.删除所有选项option

function removeAll(){
var obj=document.getElementById('mySelect');

obj.options.length=0;

}

4.删除一个选项option

function removeOne(){
var obj=document.getElementById('mySelect');

//index,要删除选项的序号,这里取当前选中选项的序号

var index=obj.selectedIndex;
obj.options.remove(index);
 
}

5.获得选项option的值

var obj=document.getElementById('mySelect');

var index=obj.selectedIndex; //序号,取当前选中选项的序号

var val = obj.options[index].value;

6.获得选项option的文本

var obj=document.getElementById('mySelect');

var index=obj.selectedIndex; //序号,取当前选中选项的序号

var val = obj.options[index].text;

7.修改选项option

var obj=document.getElementById('mySelect');

var index=obj.selectedIndex; //序号,取当前选中选项的序号

var val = obj.options[index]=new Option("新文本","新值");

8.删除select

function removeSelect(){
var mySelect = document.getElementById("mySelect");
mySelect.parentNode.removeChild(mySelect);
}

9.设置select optin被中

 

posted on   lfc0  阅读(204)  评论(0编辑  收藏  举报
努力加载评论中...
< 2025年2月 >
26 27 28 29 30 31 1
2 3 4 5 6 7 8
9 10 11 12 13 14 15
16 17 18 19 20 21 22
23 24 25 26 27 28 1
2 3 4 5 6 7 8

点击右上角即可分享
微信分享提示