<li class="number-li"><span class="sub" @click="substract">-</span><span ref="changs" class="num1">{{num}}</span><span class="ad" @click="add">+</span></li>
css:
  .number-li span {
     display: inline-block; 
    border: 2px solid rgba(0, 0, 0, 0.1);
    width: 25px;
}
.sub{
	text-align:center;
}
.num1{
	text-align:center;
	width: 25px;
	height: 25px;
       border: 2px solid rgba(0, 0, 0, 0.1);
}
.ad{
	text-align:center;
}
data:   substract(){
			if(this.num<=1)
			{
				return
			}else{
				this.num--
			}
		},add(){
		   if(this.num>=10)
		   {
			   return
		   }else{
			   this.num++
		   }
    }
原文:https://www.cnblogs.com/huanhuan55/p/9741982.html