element-ui, el-input 监听回车事件，阻止冒泡

el-form 阻止冒泡

@submit.native.prevent

例子：

<el-form :inline="true" :model="couponSearchForm" class="demo-form-inline" @submit.native.prevent>
    <el-form-item label="关键词">
        <el-input
        v-model="couponSearchForm.keyword"
        clearable
        @clear="resetCouponSearch"
        placeholder=""
        @input="autoSearchUserCoupon"
        ></el-input>
    </el-form-item>
    <el-form-item>
        <el-button type="primary" @click="searchCoupons">查询</el-button>
    </el-form-item>
</el-form>