先看效果

1.验证码组件

<template><div class="s-canvas"><canvas id="s-canvas" :width="contentWidth" :height="contentHeight" @click="Refresh"></canvas></div>
</template>
<script>
export default {name: 'SIdentify',props: {identifyCode: {type: String,default: ["a", "v", "q", "p", "y", "b", "c", "d", "e", "f", "h", "x", "z", "t", "j", "k", "l", "C", "D", "E", "F", "G", "H", "T", "Y", "U", "I", "O", "K", "L", "M", "N", "S", "A", "B"]},},data() {return {//定义容器接收验证码nums: '',fontSizeMin: 45,fontSizeMax: 35,backgroundColorMin: 180,backgroundColorMax: 240,colorMin: 50,colorMax: 160,lineColorMin: 40,lineColorMax: 180,dotColorMin: 0,dotColorMax: 255,contentWidth: 120,contentHeight: 40}},methods: {//组件通信getData() {this.$emit("getData", this.nums);},// 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() {var arr = [] //定义一个数组用来接收产生的随机数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) //图形填充颜色设置ctx.strokeStyle = this.randomColor(this.backgroundColorMin, this.backgroundColorMax) //图形轮廓的颜色设置ctx.fillRect(0, 0, this.contentWidth, this.contentHeight) //绘制一个填充的矩形 0 0 width height x起点 y起点  宽 高ctx.strokeRect(0, 0, this.contentWidth, this.contentHeight) // 绘制一个矩形边框 0 0 width height x起点 y起点  宽 高// ctx.clearRect(50,0,this.contentWidth,this.contentHeight)  //清除指定矩形区域，清除部分完全透明// 绘制文字for (let i = 0; i < 4; i++) {var index = Math.floor(Math.random() * 34);//随机索引值// var txt = identifyCode[index];this.drawText(ctx, this.identifyCode[index], i)arr[i] = this.identifyCode[index] //接收产生的随机数}this.nums = arr[0] + arr[1] + arr[2] + arr[3] //将产生的验证码放入numthis.getData();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' //字体大小ctx.textBaseline = 'alphabetic' //基线对齐let x = 20 + i * 25;// let y = 20 + 10 * Math.random();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)//移动不同位置  参数偏移量ctx.rotate(deg * Math.PI / 180) //旋转 参数角度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 < 10; i++) {ctx.strokeStyle = this.randomColor(this.lineColorMin, this.lineColorMax)ctx.beginPath() //新建一条路径ctx.moveTo(this.randomNum(0, this.contentWidth), this.randomNum(0, this.contentHeight)) //设置起点x,yctx.lineTo(this.randomNum(0, this.contentWidth), this.randomNum(0, this.contentHeight)) //绘制直线 x,y 一条当前位置到x,y点的直线ctx.stroke() // 通过线条绘制图形轮廓// ctx.closePath() //结束闭合路径}},drawDot(ctx) {// 绘制干扰点for (let i = 0; i < 120; i++) {ctx.fillStyle = this.randomColor(0, 255)ctx.beginPath()// 绘制圆弧或圆，x,y,radius，startAngle,endAngle,anticlockwise // x,y 圆心点，radius 半径，从startAngle开始到endAngle结束ctx.arc(this.randomNum(0, this.contentWidth), this.randomNum(0, this.contentHeight), 1, 0, 2 * Math.PI)ctx.fill() //通过填充路径的内容区域生成实心的图形。}},Refresh() {this.drawPic();}},watch: {identifyCode() {this.drawPic()}},mounted() {this.drawPic()}
}
</script>

2.登录组件 

	
<template>	
<div><el-form-item prop="sidentify"><el-col :span="14"><el-input placeholder="请输入验证码" type="text" v-model="yzm" ></el-input></el-col><el-col :span="8"><v-sidentify @getData="getData"></v-sidentify></el-col></el-form-item>
</div>
</template><script>import Sidentify from './yzm.vue'  //**引入验证码组件**export default {name: 'Login',data() {return {ruleForm: {usr_name: '',usr_password: '',}}},components: {'v-sidentify':Sidentify ,},methods: {getData(date){},}
</script>