<template>
      <div class="code" @click="refreshCode">
               <s-identify :identify-code="identifyCode"></s-identify>
       </div>
</template>
export default {
    components: { SIdentify: () => import('@/components/SIdentify/index') },
    data() {
        return {
            identifyCode: "",// 验证码
            identifyCodes: '123456789abcdwerwshdjeJKDHRJHKPLMKQ',//验证码随机范围
        }
    },
    mounted() {
       //组件挂载完毕刷新验证码
        this.refreshCode()
    },
    methods: {
// 验证码点击刷新方法
        refreshCode() {
            this.identifyCode = ''
// 4位验证码可以根据自己需要来定义验证码位数
            this.makeCode(this.identifyCodes, 4)
        }, 
// 随机数
        randomNum(min, max) {
            max = max + 1
            return Math.floor(Math.random() * (max - min) + min)
        },
        // 随机生成验证码字符串
        makeCode(data, len) {
            for (let i = 0; i < len; i++) {
                this.identifyCode += data[this.randomNum(0, data.length - 1)]
            }
            console.log("随机验证码:",this.identifyCode)
        }
    }
}

<template>
  <!-- 图形验证码 -->
  <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: 35
    },
    fontSizeMax: {
      type: Number,
      default: 35
    },
    backgroundColorMin: {
      type: Number,
      default: 180
    },
    backgroundColorMax: {
      type: Number,
      default: 240
    },
    colorMin: {
      type: Number,
      default: 50
    },
    colorMax: {
      type: Number,
      default: 160
    },
    lineColorMin: {
      type: Number,
      default: 100
    },
    lineColorMax: {
      type: Number,
      default: 200
    },
    dotColorMin: {
      type: Number,
      default: 0
    },
    dotColorMax: {
      type: Number,
      default: 255
    },
    contentWidth: {
      type: Number,
      default: 120
    },
    contentHeight: {
      type: Number,
      default: 40
    }
  },
  watch: {
    identifyCode() {
      this.drawPic()
    }
  },
  mounted() {
    this.drawPic()
  },
  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 + ')'
    },
    transparent() {
      return 'rgb(255,255,255)'
    },
    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.fillStyle = this.transparent()
      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)
      }
      // 绘制背景
      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(-10, 10)
      // 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 < 8; 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 < 100; 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()
      }
    }
  }
}
</script>

components: { SIdentify: () => import('@/components/SIdentify/index') }

import SIdentify from '@/components/SIdentify'
  components:{SIdentify},

import { defineComponent } from 'vue'
defineComponent({
name: 'SIdentify',
//.... 配置
})

<el-image   @click="getCode"
        style="width: 100px; height: 100px" :src="codeImage"></el-image>