vue3 element plus中el-radio选中之后再次点击取消选中问题

<template>
    <el-radio-group v-model="radioVal" @click="clickitem($event)">
    <el-radio label="1" >Option A</el-radio>
    <el-radio label="2">Option B</el-radio>
    <el-radio label="3" >Option C</el-radio>
  </el-radio-group>
</template>

<script lang="ts" setup>
import { ref } from 'vue'

const radio = ref()
const clickitem=(e)=>{
  if(e.target.tagName == 'INPUT'){        
 e.srcElement.defaultValue === radioVal.value ? (radioVal.value = "") : (radioVal.value = e.srcElement.defaultValue);
      }
    }
</script>

 <el-radio-group v-model="formData[`arr${[index]}`]">
            <el-radio
              v-for="i in item.dictValues"
              :key="i"
              :label="`${i},${item.id}`"
              @click="radioChange($event,index)"
              >{{ i }}</el-radio
            >
          </el-radio-group>
<script lang="ts">
  const radioChange= (e,index)=> {
     if(e.target.tagName == 'INPUT'){
      // console.log(23,e.srcElement.defaultValue,index,formData[`arr${[index]}`]);
      e.srcElement.defaultValue === formData[`arr${[index]}`] ? (formData[`arr${[index]}`] = "") : (formData[`arr${[index]}`] = e.srcElement.defaultValue);
    }
    }
</script>