jQuery购物车提醒问题

<script>

jQuery(function($) {

    $("#add").on("click", function() {

        var boxs = $(":checkbox[name='haitai']:checked")

        if (!boxs.length) {

            alert("请选择商品！")

        } else {

            var bao = ""

            boxs.each(function(i, dom) {

                bao += $(dom).attr("value") + "\n"

            })

            localStorage.car = localStorage.car ? bao + localStorage.car : bao

            alert("成功加入购物车！")

        }

    })

})

</script>

CGPoint point = containerView.contentOffset

CGFloat zy = point.y

CGFloat py = rect.origin.y + rect.size.height

if (py - zy <0) {

return FALSE

}

CGRect screenRect = containerView.frame

CGFloat by = screenRect.size.height + zy

if (rect.origin.y >by) {

return FALSE

}

return TRUE

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