element-ui radio 再次点击取消选中

<el-radio-group v-model="radio2">
<el-radio @click.native.prevent="clickitem(3)" :label="3"> 备选项</el-radio>
<el-radio @click.native.prevent="clickitem(6)" :label="6"> 备选项</el-radio>
<el-radio @click.native.prevent="clickitem(9)" :label="9"> 备选项</el-radio>
</el-radio-group>

clickitem (e) {
e === this.radio2 ? this.radio2 = '' : this.radio2 = e

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来源：CSDN
原文：https://blog.csdn.net/w3624270/article/details/80986967?utm_source=copy