登入註冊啥的，不需要下載外掛，上圖：

程式碼：

<template>
  <div class="about">
    <p>驗證碼：</p>
    <canvas id="canvas" width="100" height="43" @click="createCode"></canvas>
  </div>
</template>
<script>

export default {
    data(){
      return{
        sCode: "A,B,C,E,F,G,H,J,K,L,M,N,P,Q,R,S,T,W,X,Y,Z,1,2,3,4,5,6,7,8,9,0,q,w,e,r,t,y,u,i,o,p,a,s,d,f,g,h,j,k,l,z,x,c,v,b,n,m
 
",
        codeStr:[],
      }
    },
    mounted:function(){
      this.createCode()
    },
    methods:{
        //得到隨機的顏色值
        randomColor() {
            let r = Math.floor(Math.random() * 256);
            let g = Math.floor(Math.random() * 256);
            let b = Math.floor(Math.random() *
 
 256);
            return "rgb(" + r + "," + g + "," + b + ")";
        },
        // 生成二維碼
        createCode(){
            let canvas_width=document.getElementById('canvas').clientWidth;
            let canvas_height=document.getElementById('canvas').clientHeight;
            let canvas = document.getElementById(
 
"canvas");//獲取到canvas的物件，演員
            let context = canvas.getContext("2d");//獲取到canvas畫圖的環境，演員表演的舞臺
            canvas.width = canvas_width;
            canvas.height = canvas_height;
            
            let aCode = this.sCode.split(",");
            let aLength = aCode.length;//獲取到陣列的長度
                
            for (let i = 0; i <= 3; i++) {
                let j = Math.floor(Math.random() * aLength);//獲取到隨機的索引值
                let deg = Math.random() * 30 * Math.PI / 180;//產生0~30之間的隨機弧度
                let txt = aCode[j];//得到隨機的一個內容
                this.codeStr[i] = txt;
                let x = 10 + i * 20;//文字在canvas上的x座標
                let y = 20 + Math.random() * 8;//文字在canvas上的y座標
                context.font = "bold 23px 微軟雅黑";

                context.translate(x, y);
                context.rotate(deg);

                context.fillStyle = this.randomColor();
                context.fillText(txt, 0, 0);

                context.rotate(-deg);
                context.translate(-x, -y);
            }
            for (var i = 0; i <= 5; i++) { //驗證碼上顯示線條
                context.strokeStyle = this.randomColor();
                context.beginPath();
                context.moveTo(Math.random() * canvas_width, Math.random() * canvas_height);
                context.lineTo(Math.random() * canvas_width, Math.random() * canvas_height);
                context.stroke();
            }
            for (var i = 0; i <= 30; i++) { //驗證碼上顯示小點
                context.strokeStyle = this.randomColor();
                context.beginPath();
                var x = Math.random() * canvas_width;
                var y = Math.random() * canvas_height;
                context.moveTo(x, y);
                context.lineTo(x + 1, y + 1);
                context.stroke();
            }
        }
    }
}
</script>
<style scoped>
#canvas{
  border: 1px solid #aba5a5;
}
</style>