css - 如何将一个元素与 flexbox 对齐？

Question

https://jsfiddle.net/vhem8scs/

是否可以使用 flexbox 让两个元素左对齐，一个元素右对齐？该链接显示得更清楚。最后一个例子是我想要实现的。

在 flexbox 中我有一段代码。使用 float 我有四个代码块。这就是我更喜欢 flexbox 的原因之一。

HTML

<div class="wrap">
  <div>One</div>
  <div>Two</div>
  <div>Three</div>
</div>

<!-- DESIRED RESULT -->

<div class="result">
  <div>One</div>
  <div>Two</div>
  <div>Three</div>
</div>

CSS

.wrap {
  display: flex;
  background: #ccc;
  width: 100%;
  justify-content: space-between;
}

.result {
  background: #ccc;
  margin-top: 20px;
}

.result:after {
  content: '';
  display: table;
  clear: both;
}

.result div {
  float: left;
}
.result div:last-child {
  float: right;
}

Answer 1

要将一个 flex 子元素右对齐，请将其设置为margin-left: auto;

来自flex spec :

One use of auto margins in the main axis is to separate flex items into distinct "groups". The following example shows how to use this to reproduce a common UI pattern - a single bar of actions with some aligned on the left and others aligned on the right.

.wrap div:last-child {
  margin-left: auto;
}

Updated fiddle

.wrap {
  display: flex;
  background: #ccc;
  width: 100%;
  justify-content: space-between;
}
.wrap div:last-child {
  margin-left: auto;
}
.result {
  background: #ccc;
  margin-top: 20px;
}
.result:after {
  content: '';
  display: table;
  clear: both;
}
.result div {
  float: left;
}
.result div:last-child {
  float: right;
}

<div class="wrap">
  <div>One</div>
  <div>Two</div>
  <div>Three</div>
</div>

<!-- DESIRED RESULT -->
<div class="result">
  <div>One</div>
  <div>Two</div>
  <div>Three</div>
</div>

注意:

您可以通过在中间的 flex 元素上设置 flex-grow:1(或简写 flex:1)来实现类似的效果，这会将最后一个元素一直推到右边。 ( Demo )

然而，明显的区别是中间项变得比它可能需要的更大。为 flex 元素添加边框以查看差异。

Demo

.wrap {
  display: flex;
  background: #ccc;
  width: 100%;
  justify-content: space-between;
}
.wrap div {
  border: 3px solid tomato;
}
.margin div:last-child {
  margin-left: auto;
}
.grow div:nth-child(2) {
  flex: 1;
}
.result {
  background: #ccc;
  margin-top: 20px;
}
.result:after {
  content: '';
  display: table;
  clear: both;
}
.result div {
  float: left;
}
.result div:last-child {
  float: right;
}

<div class="wrap margin">
  <div>One</div>
  <div>Two</div>
  <div>Three</div>
</div>

<div class="wrap grow">
  <div>One</div>
  <div>Two</div>
  <div>Three</div>
</div>

<!-- DESIRED RESULT -->
<div class="result">
  <div>One</div>
  <div>Two</div>
  <div>Three</div>
</div>