封装Vue Element的form表单组件

前两天封装了一个基于vue和Element的table表格组件，阅读的人还是很多的，看来大家都是很认同组件化、高复用这种开发模式的，毕竟开发效率高，代码优雅，逼格高嘛。虽然这两天我的心情很糟糕，就像“懂王”怼记者：“你是一个糟糕的记者；CNN，Fake news”一样的心情，但我还是忍着难受的心情来工作和分享，毕竟工作是饭碗，分享也能化解我糟糕透顶的心情。

今天，就来分享一下基于vue和Element所封装的form表单组件，其中所用到的技术，在上一篇文章封装Vue Element的table表格组件中已介绍的差不多了，今天再来多讲一个vue的动态组件component，关于动态组件component的介绍，vue官方倒是很吝啬，就只是给了一个例子来告诉我们如何使用而已。我们可以把它理解成一个占位符，其具体展示什么，是有isattribute来实现，比如官网给的例子：

<component v-bind:is="currentTabComponent"></component>

在上述示例中，currentTabComponent可以包括：

• 已注册组件的名字

• 或一个组件的选项对象

就酱，对它的介绍完了。

如果你还想了解更多，可以去vue官网查看。

接下来就是封装的具体实现，照例先来张效果图：



1、封装的form表单组件Form.vue：

<template>
  <el-form ref="form" :model="form" :rules="rules" size="small" :label-position="'top'">
    <el-row :gutter="20">
      <el-col :lg="8" :md="12" :sm="24" v-for="(x, i) in formItems" :key="i">
        <el-form-item :label="x.label" :prop="x.prop">
          <component v-model="form[x.prop]" v-bind="componentAttrs(x)" class="width-full" />
        </el-form-item>
      </el-col>
    </el-row>
    <div class="searchBtn">
      <el-button class="filter-item" @click="reset">重置</el-button>
      <el-button class="filter-item" type="primary" @click="submit">查询</el-button>
    </div>
  </el-form>
</template>

<script>
import { fromEntries } from '@/utils'
export default {
  props: {
    config: Object,
  },
  components: {
    selectBar: {
      functional: true,
      props: {value: String, list: Array, callback: Function},
      render(h, {props: {value = '', list = [], callback}, data: {attrs = {}}, listeners: {input}}){
        return h('el-select', {class: 'width-full', props: {value, ...attrs}, on: {change(v) {input(v); callback(v)}}}, list.map(o => h('el-option', {props: {...o, key: o.value}})))
      }
    },
    checkbox: {
      functional: true,
      props: {value: Boolean, desc: String },
      render(h, {props: {value = '', desc = ''}, data: {attrs = {}}, listeners: {input}}){
        return h('el-checkbox', {props: {value, ...attrs}, on: {change(v) {input(v)}}}, desc)
      }
    },
    checkboxGroup: {
      functional: true,
      props: {value: Array, list: Array},
      render(h, {props: {value = [], list = []}, data: {attrs = {}}, listeners: {input}}){
        return h('el-checkbox-group', {props: {value, ...attrs}, on: {input(v) {input(v)}}}, list.map(o => h('el-checkbox', {props: {...o, label: o.value, key: o.value}}, [o.label])))
      }
    },
    radioGroup: {
      functional: true,
      props: {value: String, list: Array },
      render(h, {props: {value = '', list = []}, data: {attrs = {}}, listeners: {input}}){
        return h('el-radio-group', {props: {value, ...attrs}, on: {input(v) {input(v)}}}, list.map(o => h('el-radio', {props: {...o, key: o.label}}, [o.value])))
      }
    },
  },
  data(){
    let { columns, data } = this.config;

    return {
      TYPE: {
        select: {
          is: 'selectBar',
          clearable: true,   //是否可清空，默认为false不可清空
        },
        text: {
          is: 'el-input',
          clearable: true,
        },
        switch: {
          is: 'el-switch',
        },
        checkbox: {
          is: 'checkbox',
          clearable: true,
        },
        checkboxGroup: {
          is: 'checkboxGroup',
          clearable: true,
        },
        radioGroup: {
          is: 'radioGroup',
          clearable: true,
        },
        daterange: {
          is: 'el-date-picker',
          type: 'daterange',
          valueFormat: 'yyyy-MM-dd',
          rangeSeparator: '至',
          startPlaceholder: '开始日期',
          endPlaceholder: '结束日期',
          editable: false,
        },
        date: {
          is: 'el-date-picker',
          type: "date",
          valueFormat: 'yyyy-MM-dd',
          editable: false,
        },
        auto: {
          is: 'el-autocomplete'
        }
      },
      form: columns.reduce((r, c) => Object.assign(r, {[c.prop]: data[c.prop] ? data[c.prop] : (c.is == 'checkboxGroup' ? [] : null)}), {}),
      rules: columns.reduce((r, c) => ({...r, [c.prop]: c.rules ? c.rules : []}), {}),
    }
  },
  computed: {
    formItems() {
      return this.config.columns;
    },
  },
  methods: {
    componentAttrs(item) {
      let {is = 'text', label} = item, map = fromEntries(Object.entries(item).filter(n => !/^(label|prop|is|rules)/.test(n[0]))),
      placeholder = (/^(select|el-date-picker)/.test(is) ? '请选择' : '请输入') + label;

      return {...map, ...this.TYPE[is], placeholder}
    },
    reset() {
      this.$refs.form.resetFields();
    },
    submit() {
      this.$refs.form.validate(valid => valid && this.$emit('submit', this.form));
    },
    geRules(){
      let rules = {};
      this.config.columns.forEach(c => {
        let {prop, rules: ruleList = [], required = false} = c;
        rules[prop] = ruleList;
        required && ruleList.unshift({required, message: `${c.label}不能为空`});
      })
      return { rules };
    },
  }
};
</script>

<style scoped>
.width-full{width: 100%;}
</style>

在封装时有一个Object.fromEntries的方法不兼容ie，而我们公司又要求项目可以兼容ie(我们公司的ie基本都是ie11)，所以只能自己封装了一个fromEntries方法。

export const fromEntries = arr => {
  if (Object.prototype.toString.call(arr) === '[object Map]') {
    console.log(1)
    let result = {};
    for (const key of arr.keys()) {
      result[key] = arr.get(key);
    }

    return result;
  }

  if(Array.isArray(arr)){
    let result = {}
    arr.map(([key,value]) => {
      result[key] =  value
    })

    return result
  }
  throw 'Uncaught TypeError: argument is not iterable';
}

2、使用已封装的表单组件：

<template>
  <Form :config="config" @submit="getList" ref="form" />
</template>

<script>
import Form from "./Form";

const statusLlist = [
  {label: '未提交', value: "0"},
  {label: '待审批', value: "1"},
  {label: '已通过', value: "2", disabled: true}
]

export default {
  components: {
    Form,
  },
  data() {
    const confimPass = (rule, value, callback) => {
      if (value === '') {
        callback(new Error('请再次输入密码'));
      } else if (value !== this.$refs.form.form.password) {
        callback(new Error('两次输入密码不一致!'));
      } else {
        callback();
      }
    };

    return {
      config: {
        columns: [
          { prop: "name", label: "借款人名称", is: "auto", fetchSuggestions: this.querySearch },
          { prop: "certificateId", label: "统一信用代码", rules: [{required: true, message: '请输入统一信用代码'}] },
          { prop: 'date', label: "日期", is: 'date', },
          { prop: 'status', label: "状态", is: 'select', list: statusLlist, callback: r => this.statusChange(r) },
          { prop: "password", label: "密码", type: 'password' },
          { prop: "confimPass", label: "确认密码", type: 'password', rules: [{validator: confimPass}] },
          { prop: 'remark', label: "备注", type: 'textarea' },
          { prop: "email", label: "邮箱", rules: [{ required: true, message: '请输入邮箱地址' }, { type: 'email', message: '请输入正确的邮箱地址' }] },
          { prop: 'love', label: '爱好', is: 'checkboxGroup', list: [{label: '篮球', value: "0"}, {label: '排球', value: "1"}, {label: '足球', value: "2", disabled: true}] },
        ],
        data: {
          name: '小坏',
          certificateId: '222',
          status: '0',
          love: ['0']
        }
      },
    }
  },
  methods: {
    querySearch(q, cb){
      if (!q) {cb([]);return}
    },
    getList(res){
      console.log(res)
    },
    statusChange(r){
      console.log(r)
    },
  },
}
</script>

本次封装的form表单组件，基本考虑到了在日常开发中会经常使用到的表单组件，如果还有其他的需求，可自行添加。另外，本次封装也对表单的回显(返显)做了实现，比如我们在编辑数据时，需要将被修改的数据显示在表单中，本次封装就充分考虑到了这一点，只要你在传给封装的form组件的参数中加一个data参数，并将需要回显的数据名称一一对应并赋值就可以了。