发布于 2017-02-07 03:14:04 | 343 次阅读 | 评论: 0 | 来源: 网友投递
这里有新鲜出炉的Javascript教程，程序狗速度看过来！
JavaScript客户端脚本语言
Javascript 是一种由Netscape的LiveScript发展而来的原型化继承的基于对象的动态类型的区分大小写的客户端脚本语言，主要目的是为了解决服务器端语言，比如Perl，遗留的速度问题，为客户提供更流畅的浏览效果。
下面主要通过代码给大家展示下javascript记住用户名和登录密码，具体代码内容请看下文。
第一种方式：
CONTENT
login.html
welcome.html
cookie.js
common.js
login.html
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>login</title>
<script type="text/javascript" src="cookie.js"></script>
<script type="text/javascript" src="common.js"></script>
</head>
<body>
<form action="">
<p>
<span>UserName:</span>
<input id="userName" type="text" value=""/></p>
<p>
<span>Password:</span>
<input id="password" type="password" value=""/></p>
<p>
<span style="font-size:12px; color:blue;">记住密码</span>
<input id="saveCookie" type="checkbox" value="" /></p>
<p>
<input id="submit" type="button" value="GO" />
</p>
</form>
</body>
</html>
welcome.html
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>welcome</title>
</head>
<body>
<h1>Welcome!</h1>
<a href="login.html">点击返回登陆框</a>
</body>
</html>
cookie.js
//新建cookie。
//hours为空字符串时,cookie的生存期至浏览器会话结束。hours为数字0时,建立的是一个失效的cookie,这个cookie会覆盖已经建立过的同名、同path的cookie（如果这个cookie存在）。
function setCookie(name,value,hours,path){
var name = escape(name);
var value = escape(value);
var expires = new Date();
expires.setTime(expires.getTime() + hours*3600000);
path = path == "" ? "" : ";path=" + path;
_expires = (typeof hours) == "string" ? "" : ";expires=" + expires.toUTCString();
document.cookie = name + "=" + value + _expires + path;
}
//获取cookie值
function getCookieValue(name){
var name = escape(name);
//读cookie属性，这将返回文档的所有cookie
var allcookies = document.cookie;
//查找名为name的cookie的开始位置
name += "=";
var pos = allcookies.indexOf(name);
//如果找到了具有该名字的cookie，那么提取并使用它的值
if (pos != -1){ //如果pos值为-1则说明搜索"version="失败
var start = pos + name.length; //cookie值开始的位置
var end = allcookies.indexOf(";",start); //从cookie值开始的位置起搜索第一个";"的位置,即cookie值结尾的位置
if (end == -1) end = allcookies.length; //如果end值为-1说明cookie列表里只有一个cookie
var value = allcookies.substring(start,end); //提取cookie的值
return (value); //对它解码
}
else return ""; //搜索失败，返回空字符串
}
//删除cookie
function deleteCookie(name,path){
var name = escape(name);
var expires = new Date(0);
path = path == "" ? "" : ";path=" + path;
document.cookie = name + "="+ ";expires=" + expires.toUTCString() + path;
}
common.js
function $(objStr){return document.getElementByIdx_x_x(objStr);}
window.onload = function(){
//分析cookie值，显示上次的登陆信息
var userNameValue = getCookieValue("userName");
$("userName").value = userNameValue;
var passwordValue = getCookieValue("password");
$("password").value = passwordValue;
//写入点击事件
$("submit").onclick = function()
{
var userNameValue = $("userName").value;
var passwordValue = $("password").value;
//服务器验证（模拟）
var isAdmin = userNameValue == "admin" && passwordValue =="123456";
var isUserA = userNameValue == "userA" && passwordValue =="userA";
var isMatched = isAdmin || isUserA;
if(isMatched){
if( $("saveCookie").checked){
setCookie("userName",$("userName").value,24,"/");
setCookie("password",$("password").value,24,"/");
}
alert("登陆成功,欢迎你," + userNameValue + "!");
self.location.replace("welcome.html");
}
else alert("用户名或密码错误，请重新输入！");
}
}
第二种方式：
<script type="text/javascript">
window.onload=function onLoginLoaded() {
if(isPostBack == "False") {
GetLastUser();
}
}
function GetLastUser() {
var id = "49BAC005-7D5B-4231-8CEA-16939BEACD67";//GUID标识符
var usr = GetCookie(id);
if (usr != null) {
document.getElementById('txtUserName').value = usr;
}
else {
document.getElementById('txtUserName').value = "001";
}
GetPwdAndChk();
}
//点击登录时触发客户端事件
function SetPwdAndChk() {
//取用户名
var usr = document.getElementById('txtUserName').value;
alert(usr);
//将最后一个用户信息写入到Cookie
SetLastUser(usr);
//如果记住密码选项被选中
if(document.getElementById('chkRememberPwd').checked == true) {
//取密码值
var pwd = document.getElementById('txtPassword').value;
alert(pwd);
var expdate = new Date();
expdate.setTime(expdate.getTime() + 14 * (24 * 60 * 60 * 1000));
//将用户名和密码写入到Cookie
SetCookie(usr, pwd, expdate);
}
else {
//如果没有选中记住密码,则立即过期
ResetCookie();
}
}
function SetLastUser(usr) {
var id = "49BAC005-7D5B-4231-8CEA-16939BEACD67";
var expdate = new Date();
//当前时间加上两周的时间
expdate.setTime(expdate.getTime() + 14 * (24 * 60 * 60 * 1000));
SetCookie(id, usr, expdate);
}
//用户名失去焦点时调用该方法
function GetPwdAndChk() {
var usr = document.getElementById('txtUserName').value;
var pwd = GetCookie(usr);
if (pwd != null) {
document.getElementById('chkRememberPwd').checked = true;
document.getElementById('txtPassword').value = pwd;
}
else {
document.getElementById('chkRememberPwd').checked = false;
document.getElementById('txtPassword').value = "";
}
}
//取Cookie的值
function GetCookie(name) {
var arg = name + "=";
var alen = arg.length;
var clen = document.cookie.length;
var i = 0;
while (i < clen) {
var j = i + alen;
//alert(j);
if (document.cookie.substring(i, j) == arg) return getCookieVal(j);
i = document.cookie.indexOf(" ", i) + 1;
if (i == 0) break;
}
return null;
}
var isPostBack = "<%= IsPostBack %>";
function getCookieVal(offset) {
var endstr = document.cookie.indexOf(";", offset);
if (endstr == -1) endstr = document.cookie.length;
return unescape(document.cookie.substring(offset, endstr));
}
//写入到Cookie
function SetCookie(name, value, expires) {
var argv = SetCookie.arguments;
//本例中length = 3
var argc = SetCookie.arguments.length;
var expires = (argc > 2) ? argv[2] : null;
var path = (argc > 3) ? argv[3] : null;
var domain = (argc > 4) ? argv[4] : null;
var secure = (argc > 5) ? argv[5] : false;
document.cookie = name + "=" + escape(value) + ((expires == null) ? "" : ("; expires=" + expires.toGMTString())) + ((path == null) ? "" : ("; path=" + path)) + ((domain == null) ? "" : ("; domain=" + domain)) + ((secure == true) ? "; secure" : "");
}
function ResetCookie() {
var usr = document.getElementById('txtUserName').value;
var expdate = new Date();
SetCookie(usr, null, expdate);
}
</script>
</head>
<body>
<form id="form1">
<div>
用户名:<input type="text" ID="txtUserName" onblur="GetPwdAndChk()">
<input type="password" ID="txtPassword">
密码：
<input type="checkbox" ID="chkRememberPwd" />
记住密码
<input type="button" OnClick="SetPwdAndChk()" value="进入"/>
</div>
</form>
</body>以上就是用两种方式展示javascript记住用户名和登录密码的全部代码，没有来得及整理运行效果图，希望大家能够喜欢。