说明:以下内容是在ssm框架基础上实现的,请自行搭建好框架
1、下载jar包
<!-- 验证码相关 -->
<!-- https://mvnrepository.com/artifact/com.github.penggle/kaptcha -->
<dependency>
<groupId>com.github.penggle</groupId>
<artifactId>kaptcha</artifactId>
<version>2.3.2</version>
</dependency>
2、在web.xml配置
<!-- 验证码相关 -->
<servlet>
<servlet-name>Kaptcha</servlet-name>
<servlet-class>com.google.code.kaptcha.servlet.KaptchaServlet</servlet-class>
<!-- 是否有边框 -->
<init-param>
<param-name>kaptcha.border</param-name>
<param-value>no</param-value>
</init-param>
<!-- 字体颜色 -->
<init-param>
<param-name>kaptcha.textproducer.font.color</param-name>
<param-value>red</param-value>
</init-param>
<!-- 字体大小 -->
<init-param>
<param-name>kaptcha.textproducer.font.size</param-name>
<param-value>43</param-value>
</init-param>
<!-- 图片的宽度 -->
<init-param>
<param-name>kaptcha.image.width</param-name>
<param-value>135</param-value>
</init-param>
<!-- 图片的高度 -->
<init-param>
<param-name>kaptcha.image.height</param-name>
<param-value>50</param-value>
</init-param>
<!-- 使用哪些字符生成验证码 -->
<init-param>
<param-name>kaptcha.textproducer.char.String</param-name>
<param-value>ACDEFHKPRSTWX345679</param-value>
</init-param>
<!-- 干扰线的颜色-->
<init-param>
<param-name>kaptcha.noise.color</param-name>
<param-value>black</param-value>
</init-param>
<!-- 字符个数-->
<init-param>
<param-name>kaptcha.textproducer.char.length</param-name>
<param-value>4</param-value>
</init-param>
<!-- 字体-->
<init-param>
<param-name>kaptcha.textproducer.font.names</param-name>
<param-value>Arial</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>Kaptcha</servlet-name>
<url-pattern>/Kaptcha</url-pattern>
</servlet-mapping>
3、在页面中使用验证码
<li>
<div class="item-content">
<div class="item-media"><i class="icon icon-form-name"></i></div>
<div class="item-inner">
<div class="item-title label">验证码</div>
<input type="text" placeholder="验证码">
<div class="item-input">
<img id="yzm_img" title="验证码" alt="验证码" src="../Kaptcha" onclick="change_yzm(this)">
</div>
</div>
</div>
</li>
4、效果图
5、更换验证码
定义改变验证码的方法
<script type="text/javascript">
function change_yzm(img){
img.src="../Kaptcha?"+Math.floor(Math.random()*100);
}
</script>
6、校验验证码的方法
/**
* 校验验证码是否正确
* @author Mr.Feng
*
*/
public class CodeUtil {
public static boolean checkVerifyCode(HttpServletRequest request) {
String verifyCodeExpected = (String)request.getSession().getAttribute(com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);
String verifyCOdeActual = HttpServletRequestUtil.getString(request,"verifyCodeActual");
if(verifyCOdeActual==null|| !verifyCOdeActual.equals(verifyCodeExpected)) {
return false;
}
return true;
}
}