如何在 div 中垂直对齐图像

如何在包含div内部对齐图像?

在我的示例中,我需要使用class ="frame ” 将<img><div>垂直居中:

<div class="frame" style="height: 25px;">
    <img src="http://jsfiddle.net/img/logo.png" />
</div>

.frame的高度是固定的,图像的高度是未知的。如果这是唯一的解决方案,则可以在.frame添加新元素。我正在尝试在 Internet Explorer 7 和更高版本的 WebKit,Gecko 上执行此操作。

这里查看 jsfiddle。

.frame {
    height: 25px;      /* Equals maximum image height */
    line-height: 25px;
    width: 160px;
    border: 1px solid red;

    text-align: center;
    margin: 1em 0;
}
img {
    background: #3A6F9A;
    vertical-align: middle;
    max-height: 25px;
    max-width: 160px;
}
<div class=frame>
   <img src="http://jsfiddle.net/img/logo.png" height=250 />
</div>
<div class=frame>
   <img src="http://jsfiddle.net/img/logo.png" height=25 />
</div>
<div class=frame>
   <img src="http://jsfiddle.net/img/logo.png" height=23 />
</div>
<div class=frame>
   <img src="http://jsfiddle.net/img/logo.png" height=21 />
</div>
<div class=frame>
   <img src="http://jsfiddle.net/img/logo.png" height=19 />
</div>
<div class=frame>
    <img src="http://jsfiddle.net/img/logo.png" height=17 />
</div>
<div class=frame>
    <img src="http://jsfiddle.net/img/logo.png" height=15 />
 </div>
<div class=frame>
    <img src="http://jsfiddle.net/img/logo.png" height=13 />
 </div>
<div class=frame>
    <img src="http://jsfiddle.net/img/logo.png" height=11 />
 </div>
<div class=frame>
    <img src="http://jsfiddle.net/img/logo.png" height=9 />
 </div>
<div class=frame>
    <img src="http://jsfiddle.net/img/logo.png" height=7 />
 </div>
<div class=frame>
    <img src="http://jsfiddle.net/img/logo.png" height=5 />
 </div>
<div class=frame>
    <img src="http://jsfiddle.net/img/logo.png" height=3 />
 </div>

答案

据我所知,唯一(也是最好的跨浏览器)方法是在两个元素上使用height: 100%vertical-align: middleinline-block帮助器。

因此,有一个解决方案: http : //jsfiddle.net/kizu/4RPFa/4570/

.frame {
    height: 25px;      /* Equals maximum image height */
    width: 160px;
    border: 1px solid red;
    white-space: nowrap; /* This is required unless you put the helper span closely near the img */

    text-align: center;
    margin: 1em 0;
}

.helper {
    display: inline-block;
    height: 100%;
    vertical-align: middle;
}

img {
    background: #3A6F9A;
    vertical-align: middle;
    max-height: 25px;
    max-width: 160px;
}
<div class="frame">
    <span class="helper"></span><img src="http://jsfiddle.net/img/logo.png" height=250px />
</div>
<div class="frame">
    <span class="helper"></span><img src="http://jsfiddle.net/img/logo.png" height=25px />
</div>
<div class="frame">
    <span class="helper"></span><img src="http://jsfiddle.net/img/logo.png" height=23px />
</div>
<div class="frame">
    <span class="helper"></span><img src="http://jsfiddle.net/img/logo.png" height=21px />
</div>
<div class="frame">
    <span class="helper"></span><img src="http://jsfiddle.net/img/logo.png" height=19px />
</div>
<div class="frame">
    <span class="helper"></span>
    <img src="http://jsfiddle.net/img/logo.png" height=17px />
</div>
<div class="frame">
    <span class="helper"></span>
    <img src="http://jsfiddle.net/img/logo.png" height=15px />
</div>
<div class="frame">
    <span class="helper"></span>
    <img src="http://jsfiddle.net/img/logo.png" height=13px />
</div>
<div class="frame">
    <span class="helper"></span>
    <img src="http://jsfiddle.net/img/logo.png" height=11px />
</div>
<div class="frame">
    <span class="helper"></span>
    <img src="http://jsfiddle.net/img/logo.png" height=9px />
</div>
<div class="frame">
    <span class="helper"></span>
    <img src="http://jsfiddle.net/img/logo.png" height=7px />
</div>
<div class="frame">
    <span class="helper"></span>
    <img src="http://jsfiddle.net/img/logo.png" height=5px />
</div>
<div class="frame">
    <span class="helper"></span>
    <img src="http://jsfiddle.net/img/logo.png" height=3px />
</div>

或者,如果您不想在现代浏览器中添加多余的元素并且不介意使用 Internet Explorer 表达式,则可以使用伪元素,然后使用方便的表达式将其添加到 Internet Explorer,该表达式每个元素仅运行一次,因此不会有任何性能问题:

Internet Explorer 的: :beforeexpression()解决方案: http : //jsfiddle.net/kizu/4RPFa/4571/

.frame {
    height: 25px;      /* Equals maximum image height */
    width: 160px;
    border: 1px solid red;
    white-space: nowrap;

    text-align: center;
    margin: 1em 0;
}

.frame:before,
.frame_before {
    content: "";
    display: inline-block;
    height: 100%;
    vertical-align: middle;
}

img {
    background: #3A6F9A;
    vertical-align: middle;
    max-height: 25px;
    max-width: 160px;
}

/* Move this to conditional comments */
.frame {
    list-style:none;
    behavior: expression(
        function(t){
            t.insertAdjacentHTML('afterBegin','<span class="frame_before"></span>');
            t.runtimeStyle.behavior = 'none';
        }(this)
    );
}
<div class="frame"><img src="http://jsfiddle.net/img/logo.png" height=250px /></div>
<div class="frame"><img src="http://jsfiddle.net/img/logo.png" height=25px /></div>
<div class="frame"><img src="http://jsfiddle.net/img/logo.png" height=23px /></div>
<div class="frame"><img src="http://jsfiddle.net/img/logo.png" height=21px /></div>
<div class="frame"><img src="http://jsfiddle.net/img/logo.png" height=19px /></div>
<div class="frame"><img src="http://jsfiddle.net/img/logo.png" height=17px /></div>
<div class="frame"><img src="http://jsfiddle.net/img/logo.png" height=15px /></div>
<div class="frame"><img src="http://jsfiddle.net/img/logo.png" height=13px /></div>
<div class="frame"><img src="http://jsfiddle.net/img/logo.png" height=11px /></div>
<div class="frame"><img src="http://jsfiddle.net/img/logo.png" height=9px /></div>
<div class="frame"><img src="http://jsfiddle.net/img/logo.png" height=7px /></div>
<div class="frame"><img src="http://jsfiddle.net/img/logo.png" height=5px /></div>
<div class="frame"><img src="http://jsfiddle.net/img/logo.png" height=3px /></div>


怎么运行的:

  1. 当您有两个彼此相邻的inline-block元素时,您可以使它们彼此对齐,因此,使用vertical-align: middle您将得到如下所示的内容:

    两个对齐的块

  2. 当您使用固定高度的块(以pxem或其他绝对单位表示)时,可以将内部块的高度设置为%

  3. 因此,添加一个height: 100% inline-block height: 100%在高度固定的块中height: 100%将使其中的另一个inline-block元素(在您的情况下为<img/> )垂直对齐。

这可能有用:

div {
    position: relative;
    width: 200px;
    height: 200px;
}
img {
    position: absolute;
    top: 0;
    bottom: 0;
    margin: auto;
}
.image {
    min-height: 50px
}

参考: http : //www.student.oulu.fi/~laurirai/www/css/middle/

matejkramny 的解决方案是一个不错的开始,但是过大的图像比例错误。

这是我的叉子:

演示: https : //jsbin.com/lidebapomi/edit?html,css,输出

预习


HTML:

<div class="frame">
  <img src="foo"/>
</div>

CSS:

.frame {
    height: 160px; /* Can be anything */
    width: 160px; /* Can be anything */
    position: relative;
}
img {
    max-height: 100%;
    max-width: 100%;
    width: auto;
    height: auto;
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
    margin: auto;
}

三行解决方案:

position: relative;
top: 50%;
transform: translateY(-50%);

这适用于任何东西。

这里

CSS 解决方案:

.frame {
  margin: 1em 0;
  height: 35px;
  width: 160px;
  border: 1px solid red;
  position: relative;
}

img {
  max-height: 25px;
  max-width: 160px;
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  margin: auto;
  background: #3A6F9A;
}
<div class=frame>
  <img src="http://jsfiddle.net/img/logo.png" height=250 />
</div>
<div class=frame>
  <img src="http://jsfiddle.net/img/logo.png" height=25 />
</div>
<div class=frame>
  <img src="http://jsfiddle.net/img/logo.png" height=23 />
</div>
<div class=frame>
  <img src="http://jsfiddle.net/img/logo.png" height=21 />
</div>
<div class=frame>
  <img src="http://jsfiddle.net/img/logo.png" height=19 />
</div>
<div class=frame>
  <img src="http://jsfiddle.net/img/logo.png" height=17 />
</div>
<div class=frame>
  <img src="http://jsfiddle.net/img/logo.png" height=15 />
</div>
<div class=frame>
  <img src="http://jsfiddle.net/img/logo.png" height=13 />
</div>
<div class=frame>
  <img src="http://jsfiddle.net/img/logo.png" height=11 />
</div>
<div class=frame>
  <img src="http://jsfiddle.net/img/logo.png" height=9 />
</div>
<div class=frame>
  <img src="http://jsfiddle.net/img/logo.png" height=7 />
</div>
<div class=frame>
  <img src="http://jsfiddle.net/img/logo.png" height=5 />
</div>
<div class=frame>
  <img src="http://jsfiddle.net/img/logo.png" height=3 />
</div>

关键的东西

// position: relative; - in .frame holds the absolute element within the frame
// top: 0; bottom: 0; left: 0; right: 0; - this is key for centering a component
// margin: auto; - centers the image horizontally & vertically

对于更现代的解决方案,如果不需要支持旧版浏览器,则可以执行以下操作:

.frame {
    display: flex;
    /**
    Uncomment 'justify-content' below to center horizontally.
    ✪ Read below for a better way to center vertically and horizontally.
    **/

    /* justify-content: center; */
    align-items: center;
}

img {
    height: auto;

    /**
    ✪ To center this image both vertically and horizontally,
    in the .frame rule above comment the 'justify-content'
    and 'align-items' declarations,
    then  uncomment 'margin: auto;' below.
    **/

    /* margin: auto; */
}

/* Styling stuff not needed for demo */
.frame {
    max-width: 900px;
    height: 200px;
    margin: auto;
    background: #222;
}
p {
    max-width: 900px;
    margin: 20px auto 0;
}
img {
    width: 150px;
}
<div class="frame">
    <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/9988/hand-pointing.png">
</div>

这是一支钢笔: http : //codepen.io/ricardozea/pen/aa0ee8e6021087b6e2460664a0fa3f3e

这样,您可以将图像垂直居中( demo ):

div{
  height: 150px; // Internet Explorer 7 fix
  line-height: 150px;
}
img{
  vertical-align: middle;
  margin-bottom: 0.25em;
}

另外,您可以使用 Flexbox 获得正确的结果:

.parent {
  align-items: center; /* For vertical align */
  background: red;
  display: flex;
  height: 250px;
  /* justify-content: center; <- for horizontal align */
  width: 250px;
}
<div class="parent">
  <img class="child" src="https://cdn2.iconfinder.com/data/icons/social-icons-circular-black/512/stackoverflow-128.png" />
</div>

flexbox有一个超级简单的解决方案

.frame {
    display: flex;
    align-items: center;
}

您可以尝试将 PI 的 CSS 设置为display: table-cell; vertical-align: middle;