html部分

在使用过程中html部分需要在元素中定义好索要操作的数据使用data-方式锁定，这里需要注意

<view class='k-suan '>
    <view class='k-label'>班级数量</view>
    <view class='suanbox'>
      <view class='addon' data-name='classNum' bindtap='bindPlus'></view>
      <view class='cuton' data-name='classNum' bindtap='bindMinus'></view>
      <input bindinput='bindManual' data-name="classNum"  name="classNum"value='{{schoolInfo.message.classNum}}'></input>
    </view>
</view>

wxss部分

/* 计算器start */
.k-suan {
  position: relative;
  height: 80rpx;
  border-bottom: 1rpx solid #eee;
  line-height: 80rpx;
  background-color: #fff
}

.k-suan .k-label {
  width: 450rpx;
  position: absolute;
  left: 30rpx;
  top: 5rpx;
  font-size: 28rpx;
}

.k-suan .suanbox {
  width: 231rpx;
  height: 58rpx;
  background-image: url(http://wechatpx.oss-cn-beijing.aliyuncs.com/suan.png);
  background-size: 231rpx 58rpx;
  background-repeat: no-repeat;
  position: absolute;
  right: 30rpx;
  top: 12rpx;
}

.k-suan .suanbox .addon {
  width: 72rpx;
  height: 58rpx;
  position: absolute;
  right: 0;
  top: 0;
}
.k-suan .suanbox .cuton {
  width: 72rpx;
  height: 58rpx;
  position: absolute;
  left: 0;
  top: 0;
}
.k-suan .suanbox input {
  width:90rpx;
  height: 58rpx;
  position: absolute;
  right:72rpx;
  top: 0;
  text-align: center;
}
/* 计算器end */

js部分

// 计算器start
onsuanadd: function(e) {
    var now = e.currentTarget.dataset.suan
    var name = e.currentTarget.dataset.name
    now++
    this.setData({
      [name]: now
    })
},
onsuancut: function(e) {
    var now = e.currentTarget.dataset.suan
    var name = e.currentTarget.dataset.name
    if (now > 0) {
      now--
    }
    this.setData({
      [name]: now
    })
},
// 计算器end