vue3+vite3+typescript实现验证码功能及表单验证效果

<template>
  <div class="captcha" style="display: flex;">
    <canvas ref="canvas" width="100" height="40"></canvas>

  </div>
  <div class="valicode-btn">
    <el-button type="text" @click="refresh">看不清，换一张</el-button>
  </div>
</template>

<script setup lang="ts">
import { ref, onMounted } from 'Vue'
const emits = defineEmits(['getCode'])
const canvasRef = ref<htmlCanvasElement | null>(null)
const ctx = ref<CanvasRenderinGContext2D | null>(null)
const code = ref('')
const chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'
const charLength = chars.length

function getRandomChar() {
  return chars.charAt(Math.floor(Math.random() * charLength))
}

function draw() {
  if (!ctx.value) return

  ctx.value.clearRect(0, 0, canvasRef.value!.width, canvasRef.value!.height)

  let x = 10
  for (let i = 0; i < 4; i++) {
    const c = getRandomChar()
    code.value += c
    ctx.value.font = 'bold 20px Arial'
    ctx.value.fillStyle = '#333'
    ctx.value.fillText(c, x, 25)
    x += 20
  }

  for (let i = 0; i < 10; i++) {
    ctx.value.strokeStyle = '#ccc'
    ctx.value.beginPath()
    ctx.value.moveTo(Math.random() * 100, Math.random() * 40)
    ctx.value.lineTo(Math.random() * 100, Math.random() * 40)
    ctx.value.stroke()
  }
  emits('getCode', code.value)
}

function refresh() {
  code.value = ''
  draw()
  emits('getCode', code.value)
}

onMounted(() => {
  const code = ref('')
  canvasRef.value = document.querySelector('canvas')
  emits('getCode', code.value)
  ctx.value = canvasRef.value?.getContext('2d')
  draw()
})
</script>

<style scoped>
.captcha {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
}
.valicode-btn{
    height:50px;
    line-height: 50px;
}
</style>

  <div class="validate-code">
     <div style="display: flex">
       <el-fORM-item label="验证码：" prop="valicode">
          <el-input v-model="form.valicode"/>
                                                   
            </el-form-item>
          <valicode ref="refresh" @getCode="getCode"  width="150px" />
      </div>
  </div>

<script setup lang="ts">

const code = ref('')
const getCode=(value:any)=> {
    code.value = value
    console.log(value);
}

</script>

const rules=Reactive<FormRules>({
	valicode: [
    { required: true, message: '请输入验证码', trigger: 'blur' },
    { validator: checkCode, trigger: 'blur' },
    ],
})
const checkCode=(rule: any, value: any, callback: any)=>{
    console.log(code.value);
    
    if (!value) {
    return  callback(new Error('请输入验证码'))
  }
  setTimeout(() => {
    if (value != code.value) {
      callback(new Error('验证码有误，请重新输入'))
    }else {
      callback()
    }
  }, 500)
}