1. js验证码问题,如何获取随机生成的验证码的值怎么让输入的值和随机生成的验证码相比较
jsp 里面生成图片验证码的时候把那个值写到session中去,用户填写后与session里面的值比较就可以了
2. 用js进行手机号验证码要求长度是11位,只能是数字怎么做,能不用正则表达式么
首先关于手机号长度可以使用js判断用户输入长度,如果不等于11位可以进行相关提示,具体可参考以下代码
<!DOCTYPEhtml>
<html>
<head>
<metacharset="utf-8">
<title>标题</title>
<scripttype="text/javascript">
window.onload=function(){
varaIpt=document.getElementsByTagName('input')
aIpt[1].onclick=function(){
if((aIpt[0].value).length==11){
alert("您输入的长度是11位")
}
else{
alert("请进行正确的输入")
}
}
}
</script>
</head>
<body>
<inputtype="text"placeholder="请输入11位数字"name="">
<inputtype="button"value="跳转"name="">
</body>
</html>
判断用户输入的是不是数字,可以使用isNaN进行判断,具体可以参考以下代码
<!DOCTYPEhtml>
<html>
<head>
<metacharset="utf-8">
<title>标题</title>
<scripttype="text/javascript">
window.onload=function(){
varaIpt=document.getElementsByTagName('input')
aIpt[1].onclick=function(){
if((aIpt[0].value).length==11&&isNaN(aIpt[0].value)==false){
alert("您输入的长度是11位")
}
else{
alert("请进行正确的输入")
}
}
}
</script>
</head>
<body>
<inputtype="text"placeholder="请输入11位数字"name="">
<inputtype="button"value="跳转"name="">
</body>
</html>
前面的代码作为判断长度的单独展示,后面的代码,可以完整的展示限制长度和判断数字
3. JS点击图片后显示验证码 如何实现
最简单的来方法你把图一的显源示验证码也弄成一个图片,比如叫code.png,上面你的代码就能换成
<img src="code.png" onclick="this.src ={$maccms.path_tpl}picture/captcha.png"
4. 求一个能实现验证码效果的JS代码
<html>
<head>
<style type="text/css">
.code{
background-image:url(111.jpg);
font-family:Arial,宋体;
font-style:italic;
color:green;
border:0;
padding:2px 3px;
letter-spacing:3px;
font-weight:bolder;
}
.unchanged {
border:0;
}
</style>
<script language="javascript" type="text/javascript">
var code ; //在全局 定义验证码
function createCode(){
code = new Array();
var codeLength = 4;//验证码的长度
var checkCode = document.getElementById("checkCode");
checkCode.value = "";
var selectChar = new Array(2,3,4,5,6,7,8,9,'A','B','C','D','E','F','G','H','J','K','L','M','N','P','Q','R','S','T','U','V','W','X','Y','Z');
for(var i=0;i<codeLength;i++) {
var charIndex = Math.floor(Math.random()*32);
code +=selectChar[charIndex];
}
if(code.length != codeLength){
createCode();
}
checkCode.value = code;
}
function validate () {
var inputCode = document.getElementById("input1").value.toUpperCase();
if(inputCode.length <=0) {
alert("请输入验证码!");
return false;
}
else if(inputCode != code ){
alert("验证码输入错误!");
createCode();
return false;
}
else {
alert("成功!");
return true;
}
}
</script>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312"></head>
<body onLoad="createCode();">
<input type="text" id="input1" />
<input type="button" id="checkCode" class="code" style="width:60px" onClick="createCode()" /> <a href="#" onClick="createCode()">看不清楚</a>
<input id="Button1" onClick="validate();" type="button" value="确定" />
<script></script>
</body>
</html>
你要是的是不是这种效果
5. java模拟登陆js动态生成的验证码怎么获取
登录页面.jsp示例代码:
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'login.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<%
String incode = (String)request.getParameter("code");
String rightcode = (String)session.getAttribute("rCode");
if(incode != null && rightcode != null){
if(incode.equals(rightcode)){
out.println("验证码输入正确!");
}else{
out.println("验证码输入不正确,请重新输入!");
}
}
%>
<body>
<form action="login.jsp" method="post">
用户名:
<input type="text" name="username"/><br/>
密码:
<input type="password" name="password"/><br/>
验证码:
<img src="number.jsp"/>
<input type="text" name="code"/>
<input type="submit" value="登录"/>
</form>
</body>
</html>
验证码页面number.jsp代码:
<%@ page contentType="image/jpeg" language="java" import="java.util.*,java.awt.*,java.awt.image.*,javax.imageio.*" pageEncoding="utf-8"%>
<%!
Color getRandColor(int fc,int bc){
Random random = new Random();
if(fc > 255){
fc = 255;
}
if(bc < 255){
bc = 255;
}
int r = fc +random.nextInt(bc-fc);
int g = fc +random.nextInt(bc-fc);
int b = fc +random.nextInt(bc-fc);
return new Color(r,g,b);
}
%>
<%
//设置页面不缓存
response.setHeader("Pragma","no-cache");
response.setHeader("Cache-Control","no-catch");
response.setDateHeader("Expires",0);
//在内存中创建图象
int width = 60;
int height = 20;
BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
//创建图象
Graphics g = image.getGraphics();
//生成随机对象
Random random = new Random();
//设置背景色
g.setColor(getRandColor(200,250));
g.fillRect(0,0,width,height);
//设置字体
g.setFont(new Font("Tines Nev Roman",Font.PLAIN,18));
//随机产生干扰线
g.setColor(getRandColor(160,200));
for(int i = 0; i < 255; i++){
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(12);
int yl = random.nextInt(12);
}
//随机产生认证码,4位数字
String sRand = "";
for(int i = 0; i < 4; i++){
String rand = String.valueOf(random.nextInt(10));
sRand += rand;
//将认证码显示到图象中
g.setColor(new Color(20 + random.nextInt(110),20 + random.nextInt(110),20 + random.nextInt(110)));
g.drawString(rand,13*i+6,16);
}
session.setAttribute("rCode",sRand);
//图像生效
g.dispose();
//输出图像到页面
ImageIO.write(image,"JPEG",response.getOutputStream());
out.clear();
out = pageContext.pushBody();
%>
6. 如何用js写验证码程序
方法/步骤
打开网页编辑器编写div+css代码,先把界面做好,然后再做功能,代码如下所示:
<form name="form1">
请输入要产生的验证码的位数:<input type="text" name="digit" id="digit">
<br><br>
<input type="button" value="生成" onClick="deal()">
 <input type="button" value="刷新" onClick="qc()">
<br><br>
<div id="result"></div>
</form>
7. 用js如何获取验证码的值
验证复码在我们的后台代码生成,制也就是在java代码里生成。然后在页面上显示出来,当用户输入验证码后再检验用户输入的验证码是否和后台生成的验证码相同,比较的时候可以通过ajax去比较,坚决反对用个隐藏域来保存后台生成的验证码,因为这样很容易被攻击
8. 如何用JS实现登录验证码方法
<%@ page contentType="image/jpeg" import="java.awt.*,
java.awt.image.*,java.util.*,javax.imageio.*" pageEncoding="GBK"%>
<%!
Color getRandColor(int fc,int bc){//给定范围获得随机颜色
Random random = new Random();
if(fc>255) fc=255;
if(bc>255) bc=255;
int r=fc+random.nextInt(bc-fc);
int g=fc+random.nextInt(bc-fc);
int b=fc+random.nextInt(bc-fc);
return new Color(r,g,b);
}
%>
<%
//设置页面不缓存
response.setHeader("Pragma","No-cache");
response.setHeader("Cache-Control","no-cache");
response.setDateHeader("Expires", 0);// 在内存中创建图象
int width=60, height=20;
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);// 获取图形上下文
Graphics g = image.getGraphics();//生成随机类
Random random = new Random();// 设定背景色
g.setColor(getRandColor(200,250));
g.fillRect(0, 0, width, height);//设定字体
g.setFont(new Font("Times New Roman",Font.PLAIN,18));//画边框
//g.setColor(new Color());
//g.drawRect(0,0,width-1,height-1);// 随机产生155条干扰线,使图象中的认证码不易被其它程序探测到
g.setColor(getRandColor(160,200));
for (int i=0;i<155;i++)
{
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(12);
int yl = random.nextInt(12);
g.drawLine(x,y,x+xl,y+yl);
}// 取随机产生的认证码(4位数字)
String sRand="";
for (int i=0;i<4;i++){
String rand=String.valueOf(random.nextInt(10));
sRand+=rand;
// 将认证码显示到图象中
g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110)));
//调用函数出来的颜色相同,可能是因为种子太接近,所以只能直接生成
g.drawString(rand,13*i+6,16);
}// 将认证码存入SESSION
session.setAttribute("rand",sRand);// 图象生效
g.dispose();// 输出图象到页面
ImageIO.write(image, "JPEG", response.getOutputStream());
out.clear();
out = pageContext.pushBody();
%>