前端 - vue2版本代码在vue3中应该是怎样写呢？

Question

<span slot="footer" class="dialog- footer">
        <el-button type="primary" @click="dialogVisible = false">确定</el-button>
      </span>

这段代码在vue2下不会报错，但是在vue3中 slot的写法变成了v-slot，由于我刚学不久还不会改写求帮忙改写一下。整体的vue文件就是elementui拉下来的一个登录

<template>
  <div>
    <el-form ref="loginForm" :model="form" :rules="rules" label-width="80px" class="login-box">
      <h3 class="login-title">欢迎 登录</h3>
      <el-form-item label=" 账号" prop="username">
        <el-input type="text" placeholder="请输入账号" v-model="form.username"/>
      </el-form-item>
      <el-form-item label=" 密码" prop="password">
        <el-input type="password" placeholder=" 请输入密码" v-model="form.password"/>
      </el-form-item>
      <el-form-item>
        <el-button type="primary" v-on:click="onSubmit( 'loginForm' )">登录</el-button>
      </el-form-item>
    </el-form>
    <el-dialog
        title="温馨提示"
        :visible="dialogVisible"
        width="30%"
        :before-close="handLeClose">
      <span>请输入账号和密码</span>
      <span slot="footer" class="dialog- footer">
        <el-button type="primary" @click="dialogVisible = false">确定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
export default {

  // eslint-disable-next-line vue/multi-word-component-names
  name: "Login",
  data() {
    return {
      form: {
        username: '',
        password: ''
      },
      //表单验证，需要在el-form-item 元素中增加prop 属性
      rules: {
        username: [
          {required: true, message: " 账号不可为空", trigger: 'blur'}
        ],
        password: [
          {required: true, message: " 密码不可为空 ", trigger: 'blur'}
        ]
      },
      //对话框显示和隐藏
      dialogVisible: false
    }
  },
  methods: {
    onSubmit(formName) {
      //为表单绑定验证功能
      this.$refs[formName].validate((valid) => {
        if (valid) {
          //使用vue-router路由到指定页面，该方式称之为编程式导航
          this.$router.push("/main");
        } else {
          this.dialogVisible = true;
          return false;
        }
      });
    }
  }
}
</script>

<style lang="scss" scoped>
.login-box {
  border: 1px solid #DCDFE6;
  width: 350px;
  margin: 180px auto;
  padding: 35px 35px 15px 35px;
  border-radius: 5px;
  -webkit-border-radius: 5px;
  -moz-border-radius: 5px;
  box-shadow: 0 0 25px #909399;
}

.login-title {
  text-align: center;
  margin: 0 auto 40px auto;
  color: #303133;
}
</style>

Answer 1

slot="footer"改为v-slot:footer或#footer

Answer 2

https://element-plus.gitee.io/zh-CN/component/dialog.html#%E5...

官网不就是 vue3 的吗？