在这种情况下我是否正确使用了 flex？

Question

假设我想要一个看起来像这样的课程容器

让“课程”的每个部分都成为自己的弹性盒，这很糟糕吗？

.course-container {
  display: flex;
  flex-direction: column;
}

.course-options {
  display: flex;
  flex-direction: row;
  justify-content: space-between;
}

.course-title {
  display: flex;
  flex-direction: row;
  justify-content: center;
}

.course-grade {
  display: flex;
  flex-direction: row;
  justify-content: flex-end;
}

<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet" />
<div class="course-container">
  <div class="course">
    <div class="course-options">
      <i class='fa fa-pencil-square-o fa-lg' aria-hidden="true"></i>
      <i class='fa fa-trash-o fa-lg' aria-hidden="true"></i>
    </div>
    <div class="course-title">
      <a href="">Course 1</a>
    </div>
    <div class="course-grade">
      <a href="">Grade: 0.00%</a>
    </div>
  </div>
  <div class="course">
    <div class="course-options">
      <i class='fa fa-pencil-square-o fa-lg' aria-hidden="true"></i>
      <i class='fa fa-trash-o fa-lg' aria-hidden="true"></i>
    </div>
    <div class="course-title">
      <a href="">Course 2</a>
    </div>
    <div class="course-grade">
      <a href="">Grade: 0.00%</a>
    </div>
  </div>
</div>

Answer 1

你不需要在每个内部元素上定义display: flex，你可以使用align-self来代替。

.course-container,
.course {
  display: flex;
  flex-direction: column;
}

.course {
  width: 300px;
  border: 1px solid black;
  padding: 10px;
  height: 100px;
  margin: 5px;
  justify-content: space-between;
}

.course-options {
  display: flex;
  justify-content: space-between;
}

.course-title {
  align-self: center;
}

.course-grade {
  align-self: flex-end;
}

<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet" />
<div class="course-container">
  <div class="course">
    <div class="course-options">
      <i class='fa fa-pencil-square-o fa-lg' aria-hidden="true"></i>
      <i class='fa fa-trash-o fa-lg' aria-hidden="true"></i>
    </div>
    <div class="course-title">
      <a href="">Course 1</a>
    </div>
    <div class="course-grade">
      <a href="">Grade: 0.00%</a>
    </div>
  </div>
  <div class="course">
    <div class="course-options">
      <i class='fa fa-pencil-square-o fa-lg' aria-hidden="true"></i>
      <i class='fa fa-trash-o fa-lg' aria-hidden="true"></i>
    </div>
    <div class="course-title">
      <a href="">Course 2</a>
    </div>
    <div class="course-grade">
      <a href="">Grade: 0.00%</a>
    </div>
  </div>
</div>

Answer 2

你如何设置它没有任何问题，它是否是最好的很大程度上取决于course 盒子应该如何表现。

根据我现在所知道的，您可以优化该代码，我会这样做，并获得相同的结果。

在这里，我删除了所有内部包装器并使用了 auto margins，它使用 Flexbox 进行了升级，可以轻松地在其父级中对齐项目。

这样的结构的好处是，除了标记更少之外，您还有无数种方法可以根据内容或屏幕尺寸对项目进行重新排序。

堆栈sn-p

.course-container {
  display: flex;
  flex-direction: column;
}
.course {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;   /*  align to top, and prevent from stretch  */
  width: 250px;
  height: 120px;
  margin: 5px;
  border: 1px solid lightgray;
}
.course .fa-trash-o,
.course .grade {
  margin-left: auto;         /*  push trash and grade to the right  */
}
.course .grade {
  margin-top: auto;          /*  push to bottom  */
}
.course .title {
  flex-basis: 100%;          /*  take full width, make it wrap on a row of its own  */
  margin: auto 0;            /*  center vertically  */
  text-align: center;
}

<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet" />
<div class="course-container">
  <div class="course">
      <i class='fa fa-pencil-square-o fa-lg' aria-hidden="true"></i>
      <i class='fa fa-trash-o fa-lg' aria-hidden="true"></i>
      <a class='title' href="">Course 1</a>
      <a class='grade' href="">Grade: 0.00%</a>
  </div>
  <div class="course">
      <i class='fa fa-pencil-square-o fa-lg' aria-hidden="true"></i>
      <i class='fa fa-trash-o fa-lg' aria-hidden="true"></i>
      <a class='title' href="">Course 2</a>
      <a class='grade' href="">Grade: 0.00%</a>
  </div>
</div>

Answer 3

这种情况不需要 flexbox。 Flexbox 仍然有less than 90% browser support worldwide（无前缀），所以我暂时不会使用它，除非你绝对别无选择。

这是适用于所有浏览器的正确解决方案：

.card {
  text-align: center; 
  position: relative; 
  width: 100%; 
  max-width: 300px; 
  height: 100px; 
  line-height: 100px; 
  border: 1px solid black; 
  margin: 5px;
}
.card > * {line-height: 1.4em; position: absolute;}
.card > .edit {left: 0; top: 0;}
.card > .delete {right: 0; top: 0;}
.card > .grade {right: 0; bottom: 0;}

<div class="card">
  <a href="#" class="edit">edit</a>
  <a href="#" class="delete">delete</a>
  <span class="grade">grade</span>
  course 1
</div>
<div class="card">
  <a href="#" class="edit">edit</a>
  <a href="#" class="delete">delete</a>
  <span class="grade">grade</span>
  course 2
</div>