如何显示块的最后一部分的弹性？

Question

让我把reactstrap做个样品。如果想在输入后添加提示文本怎么办。我怎样才能防止 p 标签采用内联格式？

如果我有输入组并且有一个

<p class="text-muted mb-0" style="
    display: block;
">アエイオウ</p>

在最后一部分。我怎样才能让它成为一个新行的 p 标签？像这样：

.input-group {
    position: relative;
    display: flex;
    flex-wrap: wrap;
    align-items: stretch;
    width: 100%;
}
.input-group-prepend, .input-group-append {
    display: flex;
}
.input-group > .input-group-prepend > .input-group-text {
    border-top-right-radius: 0;
    border-bottom-right-radius: 0;
}
.input-group-text {
    display: -ms-flexbox;
    display: flex;
    align-items: center;
    padding: 0.375rem 0.75rem;
    margin-bottom: 0;
    font-size: 1rem;
    font-weight: 400;
    line-height: 1.5;
    color: #495057;
    text-align: center;
    white-space: nowrap;
    border: 1px solid #ced4da;
    border-radius: 0.25rem;
}

.input-group > .form-control {
    position: relative;
    -ms-flex: 1 1 auto;
    flex: 1 1 auto;
    width: 1%;
    min-width: 0;
    margin-bottom: 0;
}

.form-control {
    display: block;
    width: 100%;
    padding: 0.375rem 0.75rem;
    font-size: 1rem;
    font-weight: 400;
    line-height: 1.5;
    color: #495057;
    background-color: #fff;
    background-clip: padding-box;
    border: 1px solid #ced4da;
    border-radius: 0.25rem;
    transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
}

<div class="input-group"><div class="input-group-prepend"><span class="input-group-text">@</span></div><input type="text" placeholder="username" class="form-control"><p class="text-muted mb-0" style="
    display: block;
">アエイオウ</p></div>

Answer 1

从 .input-group class 中取出 <p>。

通过这样做，<p> 将默认为全宽。

.input-group {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: stretch;
  width: 100%;
}

.input-group-prepend,
.input-group-append {
  display: flex;
}

.input-group>.input-group-prepend>.input-group-text {
  border-top-right-radius: 0;
  border-bottom-right-radius: 0;
}

.input-group-text {
  display: -ms-flexbox;
  display: flex;
  align-items: center;
  padding: 0.375rem 0.75rem;
  margin-bottom: 0;
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.5;
  color: #495057;
  text-align: center;
  white-space: nowrap;
  border: 1px solid #ced4da;
  border-radius: 0.25rem;
}

.input-group>.form-control {
  position: relative;
  -ms-flex: 1 1 auto;
  flex: 1 1 auto;
  width: 1%;
  min-width: 0;
  margin-bottom: 0;
}

.form-control {
  display: block;
  width: 100%;
  padding: 0.375rem 0.75rem;
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.5;
  color: #495057;
  background-color: #fff;
  background-clip: padding-box;
  border: 1px solid #ced4da;
  border-radius: 0.25rem;
  transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
}

<link href="https://cdn.jsdelivr.net/npm/bootstrap@4.6.0/dist/css/bootstrap.min.css" rel="stylesheet"/>


<div class="input-group">
  <div class="input-group-prepend">
    <span class="input-group-text">@</span>
  </div>
  <input type="text" placeholder="username" class="form-control">
</div>

<!-- take the p tag out of input-group -->
<p class="text-muted mb-0 small">アエイオウ</p>

编辑：

如果您无法更改 HTML 而您必须使用 CSS，您也可以使用 flex-basis p 元素.

像这样-

.input-group {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: stretch;
  width: 100%;
}

.input-group-prepend,
.input-group-append {
  display: flex;
}

.input-group>.input-group-prepend>.input-group-text {
  border-top-right-radius: 0;
  border-bottom-right-radius: 0;
}

.input-group-text {
  display: -ms-flexbox;
  display: flex;
  align-items: center;
  padding: 0.375rem 0.75rem;
  margin-bottom: 0;
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.5;
  color: #495057;
  text-align: center;
  white-space: nowrap;
  border: 1px solid #ced4da;
  border-radius: 0.25rem;
}

.input-group>.form-control {
  position: relative;
  -ms-flex: 1 1 auto;
  flex: 1 1 auto;
  width: 1%;
  min-width: 0;
  margin-bottom: 0;
}

.form-control {
  display: block;
  width: 100%;
  padding: 0.375rem 0.75rem;
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.5;
  color: #495057;
  background-color: #fff;
  background-clip: padding-box;
  border: 1px solid #ced4da;
  border-radius: 0.25rem;
  transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
}


.text-muted {
  flex-basis: 100%;
}

<link href="https://cdn.jsdelivr.net/npm/bootstrap@4.6.0/dist/css/bootstrap.min.css" rel="stylesheet"/>


<div class="input-group">
  <div class="input-group-prepend">
    <span class="input-group-text">@</span>
  </div>
  <input type="text" placeholder="username" class="form-control">
  
  <p class="text-muted mb-0 small">アエイオウ</p>
</div>

Answer 2

https://jsfiddle.net/xj3fh4bk/6/

您的 html 代码应该是这样的：

<div class="input-group">
  <div class="input-group-prepend">
    <span class="input-group-text">@</span>
  </div>
  <input type="text" placeholder="username" class="form-control">
</div>
<p class="text-muted mb-0" style="display: block;">アエイオウ</p>

由于 .input-group 显示属性个 flex，其子项将始终排成一行。所以，你应该在 .input-group

之外使用 p 标签

如何显示块的最后一部分的弹性？

How to display block the last part of flex?

html

css

reactstrap