我喜欢@Dan Andreasson和@Robin的简单回答Métral..然而，它并不完全适用于我。

所以不要:

.grid {
display: flex;
flex-flow: row wrap;
justify-content: space-between;
}
.grid::after {
content: "";
flex: auto;
}

我使用:

.grid {
display: flex;
flex-flow: row wrap;
justify-content: space-between;
}
.grid::after {
content: "";
width: calc(100%/3 - 20px); /* whatever width grid items are */
}

到目前为止，这似乎是预期的效果。

没有任何额外的标记，只是添加::after为我指定列的宽度。

.grid {
  display:flex;
  justify-content:space-between;
  flex-wrap:wrap;
}
.grid::after{
  content: '';
  width: 10em // Same width of .grid__element
}
.grid__element{
  width:10em;
}

使用这样的HTML:

<div class=grid">
   <div class="grid__element"></div>
   <div class="grid__element"></div>
   <div class="grid__element"></div>
</div>

添加一个::之后自动填充空间。不需要污染你的HTML。下面是一个代码依赖体:http://codepen.io/DanAndreasson/pen/ZQXLXj

.grid {
  display: flex;
  flex-flow: row wrap;
  justify-content: space-between;
}

.grid::after {
  content: "";
  flex: auto;
}

你不能。Flexbox不是一个网格系统。它没有实现您所要求的功能的语言结构，至少在使用justify-content: space between时是这样。使用Flexbox最接近的方法是使用列方向，这需要设置显式的高度:

http://cssdeck.com/labs/pvsn6t4z(注:不包括前缀)

ul {
  display: flex;
  flex-flow: column wrap;
  align-content: space-between;
  height: 4em;
}

然而，只使用列会更简单，它有更好的支撑，不需要设置特定的高度:

http://cssdeck.com/labs/dwq3x6vr(注:不包括前缀)

ul {
  columns: 15em;
}

这里有一些解决方案，人们建议编写精确的布局css类，使用伪元素伪造最后一项，使用非flexbox方法等。

一个大问题是邻居之间的间隙(大小写对齐的按钮包装到多行)。在这种情况下，你不希望物品相互接触，就需要有空隙。我只是想添加一个适当的解决方案，尊重差距，并适用于任何数量的项目。它也是基于假的最后一个元素的想法，但更普遍。有关详细信息，请参阅代码片段注释。

html { font-size: 1px; } .container { font-size: 16rem; display: flex; flex-wrap: wrap; justify-content: space-between; } .item { background-color: orange; border-radius: 10rem; box-sizing: border-box; color: white; margin-bottom: 10rem; padding: 15rem 10rem; text-align: center; } <!-- Our setup from design (example) used later in calculations: container-width: 100%; (can be any) max-per-row = 4; total = 6; desired-hor-gap = 10rem; (equal to vert. gap) If you go dynamic (drawing html according to the coming data either in a backend template or in a frontend template), you have to calculate and then set exact properties inline. <i> (or any real html element) is needed to set inline styles to arrange the last row properly. "2" in <i> calc function - is 6 % 4 since calc doesn't allow for "%" operator. But in real life you will calculate these numbers in JS or some backend template anyway. Formulas written in elements' calc functions. Seem to be self-descriptive, but the idea is to set for the last fake item the remainder width + hypothetical gaps. --> <div class="container"> <div style="flex: 0 1 calc((100% - (4 - 1) * 10rem) / 4);" class="item">do stuff</div> <div style="flex: 0 1 calc((100% - (4 - 1) * 10rem) / 4);" class="item">do stuff</div> <div style="flex: 0 1 calc((100% - (4 - 1) * 10rem) / 4);" class="item">do stuff</div> <div style="flex: 0 1 calc((100% - (4 - 1) * 10rem) / 4);" class="item">do stuff</div> <div style="flex: 0 1 calc((100% - (4 - 1) * 10rem) / 4);" class="item">do stuff</div> <div style="flex: 0 1 calc((100% - (4 - 1) * 10rem) / 4);" class="item">do stuff</div> <i style="flex: 0 1 calc((100% - (4 - 1) * 10rem) / 4 * (4 - 2) + ( 4 - 2 - 1) * 10rem);"></i> </div>

如果你知道行中元素之间的空间宽度和行中元素的数量，这将工作:

例如:一行中有3个元素，元素之间的间距为10px

div:last-child:nth-child(3n+2) {
  flex-grow: 1
  margin-left: 10px
}