网站策划招聘,wordpress google推广,西安vi设计公司,店面设计怎么样验证码生成效果一#xff0c;生成验证码二#xff0c;页面收到验证码三#xff0c;验证验证码是否填写正确效果 点击验证码可切换 给出提示
一#xff0c;生成验证码
package servlet;import java.io.IOException;import javax.servlet.ServletException;
import jav…
验证码生成效果一生成验证码二页面收到验证码三验证验证码是否填写正确效果 点击验证码可切换 给出提示
一生成验证码
package servlet;import java.io.IOException;import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import cn.dsna.util.images.ValidateCode;public class ShowVerifyCode extends HttpServlet {/*** */private static final long serialVersionUID 1L;Overrideprotected void service(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {req.setCharacterEncoding(UTF-8);resp.setContentType(text/html;charsetutf-8);// 长100 宽100 4个字母 5 条干扰线的验证码ValidateCode validateCode new ValidateCode(100, 50, 4, 4);ServletOutputStream out resp.getOutputStream();String code validateCode.getCode();// 验证码字符串保存到session对象req.getSession().setAttribute(code, code);// 把验证码图片写出去validateCode.write(out);out.close();}}
二页面收到验证码 script typetext/javascript// 刷新验证码function refresh_code(obj) {// 多次请求obj.src showVerifyCode?id new Date().getMilliseconds();}function check_verify_code(obj) {var ajax new XMLHttpRequest();ajax.open(post, checkVerifyCodeServlet?verifyCode obj.value, true);ajax.onreadystatechange function() {if (ajax.readyState 4 ajax.status 200) {// response succeed...if (ajax.responseText false) {alert(验证码错误);// disable submit commit...} else {// submit... do some code...}}};ajax.send(null);}/script
图片src访问servlet接收验证码图片 form actionname: input typetext namename / br/verifyCode:input typetext nameverifyCode onblurcheck_verify_code(this)/ img srcshowVerifyCode onclickrefresh_code(this)/form三验证验证码是否填写正确 protected void service(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {Object code req.getSession().getAttribute(code);String page_code req.getParameter(verifyCode);System.out.println(生成的验证码 code \t页面验证码 page_code);PrintWriter out resp.getWriter();if (code.toString().equalsIgnoreCase(page_code)) {// 页面验证码 后台的验证码out.write(true);} else {out.write(false);}out.close();}
