数字图片验证码

1.导包

    com.github.whvcse
    easy-captcha
    1.6.2

2.controller层代码编写

//生成验证码，并存入session中
@RequestMapping("/captcha")
public void captcha(HttpServletRequest request, HttpServletResponse response) throws Exception{
    GifCaptcha gifCaptcha = new GifCaptcha(110,50,4); //设置宽度、高度、验证码数量
    CaptchaUtil.out(gifCaptcha, request, response);//生成验证码
    String verCode = gifCaptcha.text().toLowerCase();
    request.getSession().setAttribute("CAPTCHA",verCode);  //存入session
}

String sessionCode = req.getSession().getAttribute("CAPTCHA").toString();//获取生成的验证码

3.前端配置

js:

$(function(){
    init();
})

function init(){
    $.post("user/captcha");
    $("#img").attr("src","/user/captcha")
}

注意：图片路径一定要准确，是访问后端生成验证码的路径