CSS——flex 巧用伪类

一、需求描述：

图片数量不固定，一行放两个

1.图片奇数个时，最后一张图片铺满整行

2.图片偶数个时，最后一行还是一行放两个

解决思路：偶数时不变都是一行放两个，只有在奇数的时候最后一行放一个，所以只需要把奇数的最后一行宽度设置成100%

 HTML

<view class="index">
        <view class="many">
            <image
                src="https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fattach.bbs.miui.com%2Fforum%2F201408%2F07%2F200155xgo7jhigcbjcw39j.jpg&refer=http%3A%2F%2Fattach.bbs.miui.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1628513437&t=9f76c9610de34867bef45ca1ce963ca4">
            </image>
            <image
                src="https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fattach.bbs.miui.com%2Fforum%2F201408%2F07%2F200155xgo7jhigcbjcw39j.jpg&refer=http%3A%2F%2Fattach.bbs.miui.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1628513437&t=9f76c9610de34867bef45ca1ce963ca4">
            </image>
            <image
                src="https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fattach.bbs.miui.com%2Fforum%2F201408%2F07%2F200155xgo7jhigcbjcw39j.jpg&refer=http%3A%2F%2Fattach.bbs.miui.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1628513437&t=9f76c9610de34867bef45ca1ce963ca4">
            </image>
            <image
                src="https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fattach.bbs.miui.com%2Fforum%2F201408%2F07%2F200155xgo7jhigcbjcw39j.jpg&refer=http%3A%2F%2Fattach.bbs.miui.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1628513437&t=9f76c9610de34867bef45ca1ce963ca4">
            </image>
        </view>
    </view>

CSS

.index{
    padding: 0 32rpx;
}
.many{
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
}
.many image{
     48%;
    height: 336rpx;
    margin: 10rpx 0;
    border-radius: 8rpx;
}
.many image:nth-child(odd){
    &:last-child{
         100%;
    }
}