小程序开发-Now you can provide attr "wx:key" for a "wx:for" to improve performance

当我们开发微信小程序用到"wx:for"时可能会在控制台报"Now you can provide attr "wx:key" for a "wx:for" to improve performance"警告

不要慌张这只是警告不妨碍运行，消除警告只需要在"wx:for"后面添加wx:key="xxx"就行了