js实现购物车功能

<div class="service-number">
<div class="number">
<div class="clickBtn dec" [class.disabled]="formData.buyNumber<=1" (click)="formData.buyNumber=formData.buyNumber-1">
<ion-icon name="ios-remove"></ion-icon>
</div>
<span class="number">{{formData.buyNumber}}</span>
<!-- <input class="number" type="text"  [(ngModel)]="formData.buyNumber"> -->
<div class="clickBtn add" (click)="formData.buyNumber=formData.buyNumber-0+1 ">
<ion-icon name="ios-add"></ion-icon>
</div>
</div>
</div>

    .service-number{
        display: flex;
        align-items: center;
        padding-top: 20px;
        .title{
            flex: 1;
            font-size: 16px;
        }
        .number{
            .clickBtn{
                vertical-align: middle;
                text-align: center;
                border-radius: 50%;
                font-size: 20px;
                width: 25px;
                height: 25px;
                line-height: 25px;