node实现登录图片验证码的示例代码

cnpm i svg-captcha --save

var svgCaptcha = require('svg-captcha');

const cookieParase = require('cookie-parser');

app.use(cookieParase());

// 获取验证码
 getCaptcha(req, res, next){
  var captcha = svgCaptcha.create({ 
   // 翻转颜色 
   inverse: false, 
   // 字体大小 
   fontSize: 36, 
   // 噪声线条数 
   noise: 2, 
   // 宽度 
   width: 80, 
   // 高度 
   height: 30, 
  }); 
  // 保存到session,忽略大小写 
  req.session = captcha.text.toLowerCase(); 
  console.log(req.session); //0xtg 生成的验证码
  //保存到cookie 方便前端调用验证
  res.cookie('captcha', req.session); 
  res.setHeader('Content-Type', 'image/svg+xml');
  res.write(String(captcha.data));
  res.end();
 },

// 获取验证码
router.get('/api/getCaptcha', function(req, res, next) {
 return api.getCaptcha(req, res, next);
})

<img src="/api/getCaptcha" alt="captcha" >

<a href="#" rel="external nofollow" @click="editCaptcha">
  <img src="/api/getCaptcha" alt="" ref="imgYzm">
</a>

editCaptcha () {
  this.$refs.imgYzm.src = '/api/getCaptcha?d='+Math.random()
},

let captcha = document.cookie.split('=')[1]
  if(this.yzm != captcha){
   return this.$message.warning('验证码错误')
  }