kaptcha驗證碼的使用
1.首先在pom.xml文件中導入Maven依賴
<dependency>
<groupId>com.github.penggle</groupId>
<artifactId>kaptcha</artifactId>
<version>2.3.2</version>
</dependency>
2.在web.xml文件中配置一個servlet
<servlet>
<!-- 生成圖片的Servlet -->
<servlet-name>Kaptcha</servlet-name>
<servlet-class>com.google.code.kaptcha.servlet.KaptchaServlet</servlet-class>
<!-- 是否有邊框 -->
<init-param>
<param-name>kaptcha.border</param-name>
<param-value>no</param-value>
</init-param>
<!-- 字體顏色 -->
<init-param>
<param-name>kaptcha.textproducer.font.color</param-name>
<param-value>red</param-value>
</init-param>
<!-- 圖片寬度 -->
<init-param>
<param-name>kaptcha.image.width</param-name>
<param-value>135</param-value>
</init-param>
<!-- 使用哪些字符生成驗證碼 -->
<init-param>
<param-name>kaptcha.textproducer.char.string</param-name>
<param-value>ACDEFHKPRSTWX345679</param-value>
</init-param>
<!-- 圖片高度 -->
<init-param>
<param-name>kaptcha.image.height</param-name>
<param-value>50</param-value>
</init-param>
<!-- 字體大小 -->
<init-param>
<param-name>kaptcha.textproducer.font.size</param-name>
<param-value>43</param-value>
</init-param>
<!-- 干擾線的顏色 -->
<init-param>
<param-name>kaptcha.noise.color</param-name>
<param-value>black</param-value>
</init-param>
<!-- 字符個數 -->
<init-param>
<param-name>kaptcha.textproducer.char.length</param-name>
<param-value>4</param-value>
</init-param>
<!-- 使用哪些字體 -->
<init-param>
<param-name>kaptcha.textproducer.font.names</param-name>
<param-value>Arial</param-value>
</init-param>
</servlet>
<!-- 映射的url -->
<servlet-mapping>
<servlet-name>Kaptcha</servlet-name>
<url-pattern>/Kaptcha</url-pattern>
</servlet-mapping>
3.頁面代碼如下
<div class="item-inner">
<label for="j_captcha" class="item-title label">驗證碼</label>
<input id="j_captcha" name="j_captcha" type="text"
class="form-control in" placeholder="驗證碼" />
<div class="item-input">
<img id="captcha_img" alt="點擊更換" title="點擊更換"
onclick="changeVerifyCode(this)" src="../Kaptcha" />
</div>
</div>
向後端提交數據
var verifyCodeActual = $('#j_captcha').val();
if (!verifyCodeActual) {
$.toast('請輸入驗證碼!');
return;
}
formData.append("verifyCodeActual", verifyCodeActual);
4.js交互
function changeVerifyCode(img) {
img.src = "../Kaptcha?" + Math.floor(Math.random() * 100);
}
5.後端驗證
import javax.servlet.http.HttpServletRequest;
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.equalsIgnoreCase(verifyCodeExpected)) {
return false;
}
return true;
}
}
import javax.servlet.http.HttpServletRequest;
public class HttpServletRequestUtil {
public static int getInt(HttpServletRequest request, String name) {
try {
return Integer.decode(request.getParameter(name));
} catch (Exception e) {
return -1;
}
}
public static long getLong(HttpServletRequest request, String name) {
try {
return Long.valueOf(request.getParameter(name));
} catch (Exception e) {
return -1;
}
}
public static Double getDouble(HttpServletRequest request, String name) {
try {
return Double.valueOf(request.getParameter(name));
} catch (Exception e) {
return -1d;
}
}
public static Boolean getBoolean(HttpServletRequest request, String name) {
try {
return Boolean.valueOf(request.getParameter(name));
} catch (Exception e) {
return false;
}
}
public static String getString(HttpServletRequest request, String name) {
try {
String result = request.getParameter(name);
if (result != null) {
result = result.trim();
}
if ("".equals(result))
result = null;
return result;
} catch (Exception e) {
return null;
}
}
}