web开发常用js功能性小技巧
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">;
<HTML>;
<HEAD>;
<TITLE>; New Document </TITLE>;
</HEAD>;
<BODY>;
<FORM METHOD=POST ACTION="">;
<input onpaste="return false;" type="text" name="textfield" style="width:400px; ime-mode:disabled" value=" English only">;
</FORM>;
</BODY>;
</HTML>;
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只能输入数字
<script LANGUAGE="javascript">;
<!--
function check()
{
if (document.form.tell.value==""){
alert("請輸入電話號碼！");
document.form.tell.focus();
return false;
}
else{
var Letters = "0123456789()+-";
for (i=0; i< document.form.tell.value.length; i++){
var CheckChar = document.form.tell.value.charAt(i);
if (Letters.indexOf(CheckChar) == -1){
alert("電話號碼格式不正確！");
document.form.tell.focus();
return false;
}
}
}
}
//-->;
</script>;
在<body>;...</body>;之间的表单．
<form method="POST" name=form action="" onSubmit="return check();">;
<p align="center">;
请输入电话号码：<input type="text" name="tell" size="20">;
<input type="submit" value="提交" name="B1">;</p>;
</form>;
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e mail 合法性检查
function check()
{
if(document.register.email.value.length!=0)
{
if (document.register.email.value.charAt(0)=="." ||
document.register.email.value.charAt(0)=="@"||
document.register.email.value.indexOf('@', 0) == -1 ||
document.register.email.value.indexOf('.', 0) == -1 ||
document.register.email.value.lastIndexOf("@")
==document.register.email.value.length-1 ||
document.register.email.value.lastIndexOf(".")
==document.register.email.value.length-1)
{
alert("Email的格式不正確！");
document.register.email.focus();
return false;
}
}
else
{
alert("Email的不能为空！");
document.register.email.focus();
return false;
}
return false;
}
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页面右键屏蔽
<body oncontextmenu="return false">;
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自动清除输入框中的空格
再<head>;...</head>;间加入
<SCRIPT LANGUAGE="JavaScript">;
<!--//
function ignoreSpaces(string) {
var temp = "";
string = '' + string;
splitstring = string.split(" "); //双引号之间是个空格；
for(i = 0; i < splitstring.length; i++)
temp += splitstring;
return temp;
}
//-->;
</script>;
如下代码加入<body>;区
<form method="post" action="...">;
<input type=text size=25 onBlur="this.value=ignoreSpaces(this.value);" name="text">;
<input type=submit value="Ok" name="button">;
</form>;
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右键菜单的淡入淡出效果
<HTML>;<HEAD>;<TITLE>;右键菜单的淡入淡出效果</TITLE>;
<META content="text/html; charset=gb2312" http-equiv=Content-Type>;
<SCRIPT language=JavaScript>;
<!-- // RightClickMenu
var intDelay=10; //设置菜单显示速度，越大越慢
var intInterval=5; //每次更改的透明度
function showmenuie5(){
var rightedge=document.body.clientWidth-event.clientX
var bottomedge=document.body.clientHeight-event.clientY
if (rightedge<ie5menu.offsetWidth)
ie5menu.style.left=document.body.scrollLeft+event.clientX-ie5menu.offsetWidth
else
ie5menu.style.left=document.body.scrollLeft+event.clientX
if (bottomedge<ie5menu.offsetHeight)
ie5menu.style.top=document.body.scrollTop+event.clientY-ie5menu.offsetHeight
else
ie5menu.style.top=document.body.scrollTop+event.clientY
ie5menu.style.visibility="visible"
//ie5menu.style.visibility=""
ie5menu.filters.alpha.opacity=0
GradientShow()
return false
}
function hidemenuie5(){
//ie5menu.style.visibility="hidden"
GradientClose()
}
function highlightie5(){
if (event.srcElement.className=="menuitems"){
event.srcElement.style.backgroundColor="highlight"
event.srcElement.style.color="white"
}
}
function lowlightie5(){
if (event.srcElement.className=="menuitems"){
event.srcElement.style.backgroundColor=""
event.srcElement.style.color="#000000"
}
}
function jumptoie5(){
if (event.srcElement.className=="menuitems"){
if (event.srcElement.url != ''){
if (event.srcElement.getAttribute("target")!=null)
window.open(event.srcElement.url,event.srcElement.getAttribute("target"))
else
window.location=event.srcElement.url
}
}
}
function GradientShow() //实现淡入的函数
{
ie5menu.filters.alpha.opacity+=intInterval
if (ie5menu.filters.alpha.opacity<100) setTimeout("GradientShow()",intDelay)
}
function GradientClose() //实现淡出的函数
{
ie5menu.filters.alpha.opacity-=intInterval
if (ie5menu.filters.alpha.opacity>;0) {
setTimeout("GradientClose()",intDelay)
}
else {
ie5menu.style.visibility="hidden"
}
}
function ChangeBG() //改变菜单项的背景颜色，这里的两种颜色值可以改为你需要的
{
oEl=event.srcElement
if (oEl.style.background!="navy") {
oEl.style.background="navy"
}
else {
oEl.style.background="#cccccc"
}
}
// -->;
</SCRIPT>;
<style type=text/css>;
.cMenu {
FILTER: alpha(opacity=0);BACKGROUND-COLOR: #D6D3CE;BORDER-BOTTOM: #666666 2px solid; BORDER-LEFT: #E4E4E4 2px solid; BORDER-RIGHT: #666666 2px solid; BORDER-TOP: #E4E4E4 2px solid; COLOR: #000000; CURSOR: default; FONT-SIZE: 9pt; color:#000000;FONT-WEIGHT: normal; LINE-HEIGHT: 20px; POSITION: absolute; VISIBILITY: hidden; WIDTH: 110px
}
.menuitems {
font-size:9pt;
MARGIN: 2px;
PADDING-BOTTOM: 0px;
PADDING-LEFT: 15px;
PADDING-RIGHT: 3px;
PADDING-TOP: 0px;
}
</style>;
<META content="Microsoft FrontPage 4.0" name=GENERATOR>;
</HEAD>;
<BODY>;
<OBJECT classid=CLSID:8856F961-340A-11D0-A96B-00C04FD705A2 height=0 id=WebBrowser width=0>;
</OBJECT>;
<RIGHTCLICK>;<!--[if IE]>;
<DIV class=cMenu id=ie5menu onclick=jumptoie5() onmouseout=lowlightie5()
onmouseover=highlightie5()>;
<DIV class=menuitems url="javascript:click_obj(0)">;后退</DIV>;
<DIV class=menuitems url="javascript:click_obj(1)">;前进</DIV>;
<DIV class=menuhr>;<hr style="width:100%">;</DIV>;
<DIV class=menuitems url="javascript:click_obj(2)">;刷新</DIV>;
<DIV class=menuitems url="javascript:click_obj(3)">;加入收藏夹</DIV>;
<DIV class=menuitems url="javascript:click_obj(4)">;查看源文件</DIV>;
<DIV class=menuhr>;<hr style="width:100%">;</DIV>;
<DIV class=menuitems url="javascript:click_obj(5)">;属性</DIV>;
</DIV>;
<![endif]-->;
<SCRIPT language=JavaScript>;
<!--
function click_obj(id){
switch(id){
case 0:
history.back()
break
case 1:
history.forward()
break
case 2:
window.location.reload()
break
case 3:
window.external.AddFavorite(location.href, document.title)
break
case 4:
window.location = "view-source:" + window.location.href
break
case 5:
document.all.WebBrowser.ExecWB(10,1)
break
}
}
if (document.all&&window.print){
ie5menu.className="cMenu"
document.oncontextmenu=showmenuie5
document.body.onclick=hidemenuie5
}
//-->;
</SCRIPT>;
</RIGHTCLICK>;
</BODY>;</HTML>;
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ie用activex实现打印 我没有检测过版本，ie6下正常
<head>;...</head>;加入：
<SCRIPT LANGUAGE=javascript>;
<!--
function setPrint()
{
WB.ExecWB(8,1);
}
function previewPrint()
{
WB.ExecWB(7,1)
}
//-->;
</SCRIPT>;
在<body>;...</body>;加入：
<OBJECT classid=CLSID:8856F961-340A-11D0-A96B-00C04FD705A2 height=0 id=WB width=0>;
</OBJECT>;
<INPUT type="button" value="Set" id=button1 name=button1 onclick="setPrint();">;
<INPUT type="button" value="Preview" id=button2 name=button2 onclick="previewPrint();">;
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超链接提交表单
<script LANGUAGE="JavaScript">;
function checkvalue()
{
if(document.welcomeform.nickname.value=="")
{
alert("昵称不能为空！");
return(false);
}
if(document.welcomeform.password.value=="")
{
alert("密码不能为空！");
return(false);
}
document.welcomeform.submit();
return(true);
}
</script>;
在<body>;...</body>;之间加入如下代码：
<form name="welcomeform" method="post" action="welcome.asp">;
<a href="#" onclick="javascript:checkvalue();return false:">;登录</a>;
</form>;
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不允许缓存页面
使用java提供的方法，在jsp或者servlet中都可以
<%
response.setHeader("Pragma","No-cache");
response.setHeader("Cache-Control","no-cache");
response.setDateHeader("Expires", 0);
%>;
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