vue+element-ui集成随机验证码+用户名+密码的form表单验证功能

 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：

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！