<view wx:if="{{a}}">单个条件</view><view wx:if="{{a || b}}">多个或条件</view><view wx:if="{{a && b}}">多个且条件</view>
wx:if else 的判断
<view wx:if="{{a>5}}">6</view><view wx:elif="{{a < 5}}">4</view><view wx:else">5</view>