vue 实现动态表单点击新增 增加一行输入框

点击增加后会新增一行，点击每行后面的删除图标则会删除该行，新增按钮只会出现在最后一行

```

<el-col :span="12" class="mb20">

<el-form-item

:label="index == 0 ? '选择原材料' : ''"

v-for="(item, index) in form.productItemList"

:key="index"

:prop="'domains.' + index + '.value'"

>

<el-select v-model="item.name" filterable clearable placeholder="请输入原材料" @change="changeValue" @clear="clearValue">

<el-option v-for="item in productAll" :key="item.value" :label="item.name" :value="item.id" />

</el-select>

<el-input v-model="item.num" placeholder="请输入数量" style="position: absolute; left: 300px; width: 160px"></el-input>

<el-button

v-if="index !== 0"

class="mt-2"

type="danger"

style="position: absolute; left: 545px; bottom: 0px"

@click.prevent="removeDomain(domain)"

>删除</el-button

>

</el-form-item>

<el-form-item>

<el-button @click="addDomain" type="primary" style="position: absolute; left: 475px; bottom: 18px">添加</el-button>

</el-form-item>

</el-col>

```

定义方法

```

// 添加原材料

const addDomain = () => {

form.productItemList.push({

name: '',

num: '',

});

};

// 删除原材料

const removeDomain = (item: any) => {

const index = form.productItemList.indexOf(item);

if (index === -1) {

form.productItemList.splice(index, 1);

}

};

```

定义表单提交数据

```

// 提交表单数据

const form = reactive({

productItemList: [

{

name: '',

num: '',

},

],

});

```