How to embed a verification code in a website

Recently the blog Park Revision action is relatively large, see the Background Management page verification code, brought up my interest. Click the displayed verification code, you can go to a special verification code site: http://captcha.com/

It contains Java, PHP,. NET, and so on, almost full-platform support, as well as supporting tutorials and demos.

At the end of the text to provide downloaded Java version of the file, there is a jar package, how to use it? To get started quickly:

One: The simplest text verification code. Use JSP mode.

In the JSP page reference:

<% @page import="botdetect.web.Captcha"%>

Then add the following where you need the CAPTCHA:

// Adding botdetect Captcha to the page " Examplecaptcha " ); Captcha.rendercaptchamarkup (Pagecontext.getservletcontext (),     pagecontext.getout ()); %><input id="captchacodetextbox" type="text" Name="captchacodetextbox" />

Verify that the verification code entered by the user is correct

<%if("POST". Equalsignorecase (Request.getmethod ())) {  //Validate the Captcha to check if we ' re not dealing with a botBoolean Ishuman =captcha.validate (Request, Request.getparameter ("Captchacodetextbox")); if(Ishuman) {//Todo:captcha validation passed, perform protected action}Else {    //Todo:captcha validation failed, show error message  }}%>

Since the introduction of third-party jar packages, of course, it is configured in Web. Xml.

<servlet-name>botdetect captcha</servlet-name>    <servlet-class> botdetect.web.http.captchaservlet</servlet-class></servlet><servlet-mapping>    <servlet-name>botdetect captcha</servlet-name>    <url-pattern>/botdetectcaptcha</ Url-pattern></servlet-mapping>  

Two: Use Springmvc way.

The corresponding page:

<% @page contenttype= "text/html" pageencoding= "UTF-8"%><% @taglib prefix= "Botdetect" uri= "Botdetect"%> <! DOCTYPE HTML PUBLIC "-//w3c//dtd HTML 4.01 transitional//en" "Http://www.w3.org/TR/html4/loose.dtd" > for= "Captchacodetextbox"class= "Prompt" >Retype the code from the picture:</label> <!--Adding botdetect Captcha to the page-to <botdetect:captcha id= "Basicexamplecap Tcha "/> <divclass= "Validationdiv" > <input id= "captchacodetextbox" type= "text"name= "Captchacodetextbox"value= "${basicexample.captchacodetextbox}"/> <input type= "Submit" name= "submit" value= "Submit"/>&nbsp; <spanclass= "correct" >${basicExample.captchaCodeCorrect}</span> <spanclass= "Incorrect" >${basicExample.captchaCodeIncorrect}</span> </div> </fieldset> </form&  Gt </body>
Controller for the page:
 PackageBotdetect.examples.springmvc.basic.controller;Importbotdetect.examples.springmvc.basic.model.BasicExample;ImportBotdetect.web.Captcha;Importjavax.servlet.http.HttpServletRequest;ImportJavax.servlet.http.HttpServletResponse;Importorg.springframework.validation.BindException;ImportOrg.springframework.web.servlet.ModelAndView;ImportOrg.springframework.web.servlet.mvc.SimpleFormController; Public classIndexcontrollerextendsSimpleformcontroller { PublicIndexcontroller () {Setcommandclass (basicexample.class); } @OverrideprotectedModelandview OnSubmit (httpservletrequest request, httpservletresponse response, Object command, bindexception E rrors) {basicexample basicexample=(basicexample) command; //Validate the Captcha to check if we ' re not dealing with a botCaptcha Captcha = captcha.load (Request, "Basicexamplecaptcha"); BooleanIshuman =captcha.validate (Request, Basicexample.getcaptchacodetextbox ()); if(Ishuman) {Basicexample.setcaptchacodecorrect ("Correct."); Basicexample.setcaptchacodeincorrect (""); } Else{basicexample.setcaptchacodecorrect (""); Basicexample.setcaptchacodeincorrect ("Incorrect!"); } basicexample.setcaptchacodetextbox (""); return NewModelandview ("index", "Basicexample", basicexample); }  }
The bean corresponding to the verification code
 PackageBotdetect.examples.springmvc.basic.model; Public classBasicexample {PrivateString Usercaptchacode, Captchacodecorrect, Captchacodeincorrect;  PublicString Getcaptchacodetextbox () {returnUsercaptchacode; }   Public voidSetcaptchacodetextbox (String usercaptchacode) { This. Usercaptchacode =Usercaptchacode; }   PublicString Getcaptchacodecorrect () {returnCaptchacodecorrect; }   Public voidSetcaptchacodecorrect (String captchacodecorrect) { This. Captchacodecorrect =Captchacodecorrect; }   PublicString Getcaptchacodeincorrect () {returnCaptchacodeincorrect; }   Public voidSetcaptchacodeincorrect (String captchacodeincorrect) { This. Captchacodeincorrect =Captchacodeincorrect; }}
Download the Captcha file:
Http://captcha.com/botdetect-java-captcha-component-free.zip
How to embed a verification code in a website