html

<el-select :popper-append-to-body="false" center filterable v-model="formData.selectVal" @change="getProjectClassFn('')" size="mini" clearable ref="refSelectVal">
                    <el-option v-for="(item, i) in List" :key="i" :label="item.label" :value="item.value"></el-option>
                </el-select>

data

list:[
{label:'文字0',value:0},
{label:'文字1',value:1},
{label:'文字2',value:2},
]

直接监听值变化，nexttick是为了渲染后才能获取得到label

	watch: {
        'formData.selectVal':function(){
            this.$nextTick(function(){
                console.log(this.$refs.refSelectVal.selectedLabel)
            })
        },
    },