vue实现随机验证码功能

效果图：

1.html代码

<div class="form-group" style="display: flex;">
                    <div>
                        <span>验证码：</span>
                        <input type="text" id="code" v-model="code" class="code"  placeholder="请输入您的验证码" />
                    </div>
                  <div class="login-code" @click="refreshCode">
            <!--验证码组件-->
            <s-identify :identifyCode="identifyCode"></s-identify>
            </div>
                </div>

2.css样式

/*验证码样式*/
.code{
    width:124px;
    height:31px;
    border:1px solid rgba(186,186,186,1);
}
.login-code{
     cursor: pointer;
}

3.js引入验证码组件,并且定义三个变量。

import SIdentify  from '../components/sidentify'

components: { SIdentify },
data () {
    return {
      identifyCodes: "1234567890",
      identifyCode: "",
      code:"",//text框输入的验证码
    }
}, 

4.mounted里的代码

mounted(){
    this.identifyCode = "";
    this.makeCode(this.identifyCodes, 4);
},

5.在created里初始化验证码

6.methods里添加以下方法。

//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)
        ];
    }
    console.log(this.identifyCode);
},

在提交表单的时候对验证码进行判断。

sidentify.vue组件代码：

代码：

<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: 112
        },
        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>

这篇文章是我参考别人写的，很感谢那个博主。

 登录功能带验证码的例子：https://www.jianshu.com/p/99c6e2f3e457