在登入页面，我们往往需要通过输入验证码才能进行登入，那我们下面就详讲一下在vue项目中如何配合element-ui实现这个功能

第一步：自定义一个生产随机验证码的组件，其本质是使用canvas绘制，详细代码如下：

<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: 16 }, fontSizeMax: { type: Number, default: 40 }, backgroundColorMin: { type: Number, default: 180 }, backgroundColorMax: { type: Number, default: 240 }, colorMin: { type: Number, default: 50 }, colorMax: { type: Number, default: 160 }, lineColorMin: { type: Number, default: 40 }, lineColorMax: { type: Number, default: 180 }, dotColorMin: { type: Number, default: 0 }, dotColorMax: { type: Number, default: 255 }, contentWidth: { type: Number, default: 112 }, contentHeight: { type: Number, default: 38 } }, 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) { var r = this.randomNum(min, max) var g = this.randomNum(min, max) var b = this.randomNum(min, max) return 'rgb(' + r + ',' + g + ',' + b + ')' }, drawPic() { var canvas = document.getElementById('s-canvas') var 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' var x = (i + 1) * (this.contentWidth / (this.identifyCode.length + 1)) var 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 < 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() } } }, watch: { identifyCode() { this.drawPic() } }, mounted() { this.drawPic() }}</script>

第二步：使用该组件：

我们首先新建一个vue组件，在该组件进行布局，其中还包括用户名和密码的验证（这只是前端的简单验证，真实项目中还需要请求登入接口进行后端验证）

<template> <el-form class="login-form" status-icon :rules="loginRules" ref="loginForm" :model="loginForm" label-width="0"> <el-form-item prop="username"> <el-input size="small" @keyup.enter.native="handleLogin" v-model="loginForm.username" auto-complete="off" placeholder="请输入用户名"> <i slot="prefix" class="icon-yonghu"></i> </el-input> </el-form-item> <el-form-item prop="password"> <el-input size="small" @keyup.enter.native="handleLogin" :type="passwordType" v-model="loginForm.password" auto-complete="off" placeholder="请输入密码"> <i class="el-icon-view el-input__icon" :style="fontstyle" slot="suffix" @click="showPassword"></i> <i slot="prefix" class="icon-mima"></i> </el-input> </el-form-item> <el-form-item prop="verifycode"> <!-- 注意：prop与input绑定的值一定要一致，否则验证规则中的value会报undefined，因为value即为绑定的input输入值 --> <el-input v-model="loginForm.verifycode" placeholder="请输入验证码" class="identifyinput"></el-input> </el-form-item> <el-form-item> <div class="identifybox"> <div @click="refreshCode"> <s-identify :identifyCode="identifyCode"></s-identify> </div> <el-button @click="refreshCode" type='text' class="textbtn">看不清，换一张</el-button> </div> </el-form-item> <el-checkbox v-model="checked">记住账号</el-checkbox> <el-form-item> <el-button type="primary" size="small" @click.native.prevent="handleLogin" class="login-submit">登录</el-button> </el-form-item> </el-form></template>

第三步：生产随机码与进行登入验证

<script>import { isvalidUsername } from '@/utils/validate'import SIdentify from '@/components/identify/identify.vue'export default { name: 'userlogin', data() { // 用户名自定义验证规则 const validateUsername = (rule, value, callback) => { if (!isvalidUsername(value)) { callback(new Error('请输入正确的用户名')) } else { console.log('user', value) callback() } } // 验证码自定义验证规则 const validateVerifycode = (rule, value, callback) => { if (value === '') { callback(new Error('请输入验证码')) } else if (value !== this.identifyCode) { console.log('validateVerifycode:', value) callback(new Error('验证码不正确!')) } else { callback() } } return { fontstyle: { }, loginForm: { username: 'admin', password: '123456', verifycode: '' }, checked: false, identifyCodes: '1234567890', identifyCode: '', loginRules: { // 绑定在form表单中的验证规则 username: [ { required: true, trigger: 'blur', validator: validateUsername } ], password: [ { required: true, message: '请输入密码', trigger: 'blur' }, { min: 6, message: '密码长度最少为6位', trigger: 'blur' } ], verifycode: [ { required: true, trigger: 'blur', validator: validateVerifycode } ] }, passwordType: 'password' } }, components: { SIdentify }, created() { }, mounted() { // 验证码初始化 this.identifyCode = '' this.makeCode(this.identifyCodes, 4) }, computed: { }, props: [], methods: { // 通过改变input的type使密码可见 showPassword() { this.fontstyle === '' ? (this.fontstyle = 'color: red') : (this.fontstyle = '') // 改变密码可见按钮颜色 this.passwordType === '' ? (this.passwordType = 'password') : (this.passwordType = '') }, // 点击登入按钮 handleLogin() { this.$refs.loginForm.validate(valid => { if (valid) { this.$store.dispatch('Login', this.loginForm).then(res => { this.$router.push({ path: '/dashboard/dashboard' }) }) } }) }, // 生成随机数 randomNum(min, max) { return Math.floor(Math.random() * (max - min) + min) }, // 切换验证码 refreshCode() { this.identifyCode = '' this.makeCode(this.identifyCodes, 4) }, // 生成四位随机验证码 makeCode(o, l) { for (let i = 0; i < l; i++) { this.identifyCode += this.identifyCodes[ this.randomNum(0, this.identifyCodes.length) ] } console.log(this.identifyCode) } }}</script><style scoped>.identifybox{ display: flex; justify-content: space-between; margin-top:7px;}.iconstyle{ color:#409EFF;}</style>

最后的效果如下，当我们输入之后鼠标失去焦点就会进行验证：

总结

以上所述是小编给大家介绍的vue+element-ui集成随机验证码+用户名+密码的form表单验证功能，希望对大家有所帮助，如果大家有任何疑问欢迎给我留言，小编会及时回复大家的！