(1)在maven的配置文件pom.xml中添加依赖
<dependency>
<groupId>com.github.penggle</groupId>
<artifactId>kaptcha</artifactId>
<version>2.3.2</version>
</dependency>
(2)在web的配置文件web.xml中添加,配置验证码的一些属性
<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>
<!-- 图片宽度 -->
<init-param>
<param-name>kaptcha.image.width</param-name>
<param-value>135</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>
<!-- 图片高度 -->
<init-param>
<param-name>kaptcha.image.height</param-name>
<param-value>50</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>
<!-- 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)html中的写法
<li>
<div class="item-content">
<div class="item-inner">
<div class="item-title label">验证码</div>
<input type="text" id="j_captcha" placeholder="验证码">
<div class="item-input">
<img id="captcha_img" alt="点击更换" title="点击更换"
onclick="changeVerifyCode(this)" src="../Kaptcha" />
</div>
</div>
</div>
</li>
(4)点击更换验证码的实现changeVerifyCode(this)
在js中写入
function changeVerifyCode(img) {
img.src = "../Kaptcha?" + Math.floor(Math.random() * 100);
}
(5)将获取到的验证码传入到后台,首先通过标签id获取值,然后将这个值封装到formData中,传入到后台
var verifyCodeActual = $('#j_captcha').val();
if (!verifyCodeActual) {
$.toast('请输入验证码!');
return;
}
formData.append('verifyCodeActual', verifyCodeActual);
(6)在后端写一个工具类,看输入的验证码是否正确
public class CodeUtil {
/**
* 检查验证码是否和预期相符
*
* @param request
* @return
*/
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;
}
}
(7)工具类的使用
if (!CodeUtil.checkVerifyCode(request)) {
modelMap.put("success", false);
modelMap.put("errMsg", "输入了错误的验证码");
return modelMap;
}
(8)现在出现一个问题就是验证码错误,需要在引入一些流和文件上传的类库
在pom.xml中加入
Pom.xml
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.3.2</version>
</dependency>
在web.xml中加入
<bean id="multipartResolver"
class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<property name="defaultEncoding" value="utf-8"></property>
<!-- 1024 * 1024 * 20 = 20M -->
<property name="maxUploadSize" value="20971520"></property>
<property name="maxInMemorySize" value="20971520"></property>
</bean>