vue-动态验证码

<el-input type="text" placeholder="请输入验证码" class="code" @blur="checkLpicma" v-model="code" autoComplete="off" @keyup.enter.native="login"/>
                <div class="login-code" @click="refreshCode">
                  <!--验证码组件-->
                  <s-identify :identifyCode="identifyCode"></s-identify>
                </div>

<el-button @click.native.prevent="login" @keyup.enter="login" type="primary">登录</el-button>

　　

import SIdentify from '@/components/sidentify'
components: {
    SIdentify
  },
data () {
    return {
      loginFailedNum: 1,
      identifyCodes: '1234567890ABCDFEG',
      identifyCode: '',
      code: '', // text框输入的验证码
    }
},
mounted () {
    this.refreshCode()
    this.identifyCode = ''
    this.makeCode(this.identifyCodes, 4)
},
methods: {
    // 图片验证码
    randomNum (min, max) {
      return Math.floor(Math.random() * (max - min) + min)
    },
    refreshCode () {
      this.identifyCode = ''
      this.makeCode(this.identifyCodes, 4)
    },
    makeCode (o, l) {
      for (let i = 0; i < l; i++) {
        this.identifyCode += this.identifyCodes[this.randomNum(0, this.identifyCodes.length)]
      }
    },
    checkLpicma () {
      if (this.code == '') {
        this.$message({
          message: '请输入验证码',
          type: 'error'
        })
      } else if (this.code !== this.identifyCode) {
        this.$message({
          message: '验证码不正确',
          type: 'error'
        })
        this.refreshCode()
        this.code = ''
      } else {
        localStorage.setItem('loginFailedNum', 1)
      }
    },
    login () { // 密码登录
        this.checkLpicma()
    }
}

　　

.code{
  70% !important;
  float: left;
}
.login-code{
   20%;
  float: left;
  cursor: pointer;
}

<template>
    <div class="s-canvas">
        <canvas id="s-canvas" :width="contentWidth" :height="contentHeight"></canvas>
    </div>
</template>
<script>
export default {
  name: 'SIdentify',
  props: {
    identifyCode: {
      type: String,
      default: '1234'
    },
    fontSizeMin: {
      type: Number,
      default: 25
    },
    fontSizeMax: {
      type: Number,
      default: 30
    },
    backgroundColorMin: {
      type: Number,
      default: 255
    },
    backgroundColorMax: {
      type: Number,
      default: 255
    },
    colorMin: {
      type: Number,
      default: 0
    },
    colorMax: {
      type: Number,
      default: 160
    },
    lineColorMin: {
      type: Number,
      default: 100
    },
    lineColorMax: {
      type: Number,
      default: 255
    },
    dotColorMin: {
      type: Number,
      default: 0
    },
    dotColorMax: {
      type: Number,
      default: 255
    },
    contentWidth: {
      type: Number,
      default: 100
    },
    contentHeight: {
      type: Number,
      default: 31
    }
  },
  methods: {
    // 生成一个随机数
    randomNum (min, max) {
      return Math.floor(Math.random() * (max - min) + min)
    },
    // 生成一个随机的颜色
    randomColor (min, max) {
      let r = this.randomNum(min, max)
      let g = this.randomNum(min, max)
      let b = this.randomNum(min, max)
      return 'rgb(' + r + ',' + g + ',' + b + ')'
    },
    drawPic () {
      let canvas = document.getElementById('s-canvas')
      let ctx = canvas.getContext('2d')
      ctx.textBaseline = 'bottom'
      // 绘制背景
      ctx.fillStyle = this.randomColor(this.backgroundColorMin, this.backgroundColorMax)
      ctx.fillRect(0, 0, this.contentWidth, this.contentHeight)
      // 绘制文字
      for (let i = 0; i < this.identifyCode.length; i++) {
        this.drawText(ctx, this.identifyCode[i], i)
      }
      this.drawLine(ctx)
      this.drawDot(ctx)
    },
    drawText (ctx, txt, i) {
      ctx.fillStyle = this.randomColor(this.colorMin, this.colorMax)
      ctx.font = this.randomNum(this.fontSizeMin, this.fontSizeMax) + 'px SimHei'
      let x = (i + 1) * (this.contentWidth / (this.identifyCode.length + 1))
      let y = this.randomNum(this.fontSizeMax, this.contentHeight - 5)
      var deg = this.randomNum(-45, 45)
      // 修改坐标原点和旋转角度
      ctx.translate(x, y)
      ctx.rotate(deg * Math.PI / 180)
      ctx.fillText(txt, 0, 0)
      // 恢复坐标原点和旋转角度
      ctx.rotate(-deg * Math.PI / 180)
      ctx.translate(-x, -y)
    },
    drawLine (ctx) {
      // 绘制干扰线
      for (let i = 0; i < 5; i++) {
        ctx.strokeStyle = this.randomColor(this.lineColorMin, this.lineColorMax)
        ctx.beginPath()
        ctx.moveTo(this.randomNum(0, this.contentWidth), this.randomNum(0, this.contentHeight))
        ctx.lineTo(this.randomNum(0, this.contentWidth), this.randomNum(0, this.contentHeight))
        ctx.stroke()
      }
    },
    drawDot (ctx) {
      // 绘制干扰点
      for (let i = 0; i < 80; i++) {
        ctx.fillStyle = this.randomColor(0, 255)
        ctx.beginPath()
        ctx.arc(this.randomNum(0, this.contentWidth), this.randomNum(0, this.contentHeight), 1, 0, 2 * Math.PI)
        ctx.fill()
      }
    }
  },
  watch: {
    identifyCode () {
      this.drawPic()
    }
  },
  mounted () {
    this.drawPic()
  }
}
</script>
<style scoped>
.s-canvas {
    height: 38px;
}
.s-canvas canvas{
    /* margin-top: 1px;
    margin-left: 8px; */
}
</style>

登录功能带验证码的例子：https://www.jianshu.com/p/99c6e2f3e457        https://www.cnblogs.com/web-aqin/archive/2019/04/30/10796326.html