input 判断不能输入小于0

<input v-model="each.realBuyCount" :disabled="nonebg" type="number"  @blur="sumFocus($event)"/>
sumFocus(e){
    if(e.target.value<=0){
        e.target.value =""
        return false
          }else{
          e.target.value =e.target.value
          }
},