URL rewriting to implement verification code transformation
Rewriting URL mechanism: In order to ensure that the address of a URL is unique, the parameters passed to the server can be different each time. Here, when implementing the function of changing the verification code, the value of the parameter list is changed to refresh. Please refer to this article for the detailed code
Rewriting URL mechanism: In order to ensure that the address of a URL is unique, the parameters passed to the server can be different each time.
The header information of the data request can be analyzed: the header information includes http protocol, IP address, port number, project name, and request parameter list. If the resources you want to access do not change, you can only change the parameters. Continuous table.
When implementing the function of changing the verification code, the value of the parameter list is changed to refresh.
Detailed code implementation:
<%@page import="javax.imageio.ImageIO"%>
<%@page import="java.awt.Font"%>
<%@page import="java.awt.Color"%>
<%@page import="java.awt.Graphics"%>
<%@page import="java.awt.image.BufferedImage"%>
<%@ page contentType="image/jpeg" language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
int w=100;
int h=30;
BufferedImage bi=new BufferedImage(w,h,BufferedImage.TYPE_INT_RGB);
Graphics g=bi.getGraphics();
Color c=g.getColor();
Font f=g.getFont();
Random r=new Random();
Color bg=new Color(150+r.nextInt(100),150+r.nextInt(100),150+r.nextInt(100));
g.setColor(bg);
g.fillRect(0, 0, w, h);
String code="";
for(int i=1;i<=4;i++){
int num=r.nextInt(10);
code=code+num;
Color num_c=new Color(r.nextInt(150),r.nextInt(150),r.nextInt(150));
g.setColor(num_c);
g.drawString(String.valueOf(num), 20*i, h/2);
}
request.getSession().setAttribute("code", code);
//清空缓存
response.setHeader("pragma", "bo-cache");
response.setHeader("cache-control", "bo-cache");
response.addDateHeader("expires", 0);
ImageIO.write(bi, "jpeg", response.getOutputStream());
out.close();
%>Add login page:
<%@ page contentType="text/html; charset=utf-8" 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%>" rel="external nofollow" >
<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" rel="external nofollow" >
-->
<script type="text/javascript">
function changeimage(){
var d=new Date();//生成时间戳，
document.getElementById("img").src="image.jsp?t="+d;//由变化的时间使参数连表发生变化，url重写
}
</script>
</head>
<body>
<font color="red">${requestScope.msg }</font>
<form action="loginServlet" method="post">
name:<input type="text" name="uname"><br>
pwd:<input type="pwd" name="upwd"><br>
code:<input type="text" name="code" size="5"><img id="img" alt="" src="image.jsp "><a onclick="changeimage()">换一张</a><br>
<input type="submit" >
</form>
</body>
</html>Use of time changes , each time a timestamp is generated and passed to the requested URL, the purpose of rewriting the URL is achieved, thus realizing the refresh function of changing one page.
The above is the detailed content of URL rewriting to implement verification code transformation. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
AI Hentai Generator
Generate AI Hentai for free.
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
1386
52
How to verify signature in PDF
Feb 18, 2024 pm 05:33 PM
We usually receive PDF files from the government or other agencies, some with digital signatures. After verifying the signature, we see the SignatureValid message and a green check mark. If the signature is not verified, the validity is unknown. Verifying signatures is important, let’s see how to do it in PDF. How to Verify Signatures in PDF Verifying signatures in PDF format makes it more trustworthy and the document more likely to be accepted. You can verify signatures in PDF documents in the following ways. Open the PDF in Adobe Reader Right-click the signature and select Show Signature Properties Click the Show Signer Certificate button Add the signature to the Trusted Certificates list from the Trust tab Click Verify Signature to complete the verification Let
Detailed method to unblock using WeChat friend-assisted verification
Mar 25, 2024 pm 01:26 PM
1. After opening WeChat, click the search icon, enter WeChat team, and click the service below to enter. 2. After entering, click the self-service tool option in the lower left corner. 3. After clicking, in the options above, click the option of unblocking/appealing for auxiliary verification.
How to implement dual WeChat login on Huawei mobile phones?
Mar 24, 2024 am 11:27 AM
How to implement dual WeChat login on Huawei mobile phones? With the rise of social media, WeChat has become one of the indispensable communication tools in people's daily lives. However, many people may encounter a problem: logging into multiple WeChat accounts at the same time on the same mobile phone. For Huawei mobile phone users, it is not difficult to achieve dual WeChat login. This article will introduce how to achieve dual WeChat login on Huawei mobile phones. First of all, the EMUI system that comes with Huawei mobile phones provides a very convenient function - dual application opening. Through the application dual opening function, users can simultaneously
PHP Programming Guide: Methods to Implement Fibonacci Sequence
Mar 20, 2024 pm 04:54 PM
The programming language PHP is a powerful tool for web development, capable of supporting a variety of different programming logics and algorithms. Among them, implementing the Fibonacci sequence is a common and classic programming problem. In this article, we will introduce how to use the PHP programming language to implement the Fibonacci sequence, and attach specific code examples. The Fibonacci sequence is a mathematical sequence defined as follows: the first and second elements of the sequence are 1, and starting from the third element, the value of each element is equal to the sum of the previous two elements. The first few elements of the sequence
How to implement the WeChat clone function on Huawei mobile phones
Mar 24, 2024 pm 06:03 PM
How to implement the WeChat clone function on Huawei mobile phones With the popularity of social software and people's increasing emphasis on privacy and security, the WeChat clone function has gradually become the focus of people's attention. The WeChat clone function can help users log in to multiple WeChat accounts on the same mobile phone at the same time, making it easier to manage and use. It is not difficult to implement the WeChat clone function on Huawei mobile phones. You only need to follow the following steps. Step 1: Make sure that the mobile phone system version and WeChat version meet the requirements. First, make sure that your Huawei mobile phone system version has been updated to the latest version, as well as the WeChat App.
New features in PHP 8: Added verification and signing
Mar 27, 2024 am 08:21 AM
PHP8 is the latest version of PHP, bringing more convenience and functionality to programmers. This version has a special focus on security and performance, and one of the noteworthy new features is the addition of verification and signing capabilities. In this article, we'll take a closer look at these new features and their uses. Verification and signing are very important security concepts in computer science. They are often used to ensure that the data transmitted is complete and authentic. Verification and signatures become even more important when dealing with online transactions and sensitive information because if someone is able to tamper with the data, it could potentially
Master how Golang enables game development possibilities
Mar 16, 2024 pm 12:57 PM
In today's software development field, Golang (Go language), as an efficient, concise and highly concurrency programming language, is increasingly favored by developers. Its rich standard library and efficient concurrency features make it a high-profile choice in the field of game development. This article will explore how to use Golang for game development and demonstrate its powerful possibilities through specific code examples. 1. Golang’s advantages in game development. As a statically typed language, Golang is used in building large-scale game systems.
PHP Game Requirements Implementation Guide
Mar 11, 2024 am 08:45 AM
PHP Game Requirements Implementation Guide With the popularity and development of the Internet, the web game market is becoming more and more popular. Many developers hope to use the PHP language to develop their own web games, and implementing game requirements is a key step. This article will introduce how to use PHP language to implement common game requirements and provide specific code examples. 1. Create game characters In web games, game characters are a very important element. We need to define the attributes of the game character, such as name, level, experience value, etc., and provide methods to operate these
