如何在CSS中垂直对齐所有文本? [英] How to vertically align all text in CSS?

问题描述

问题似乎是某些字母，例如g，y，q等，其尾巴向下倾斜，因此不允许垂直居中.这是展示问题的图像.

The issue seems to be that certain letters like g, y, q, etc. that have a tail that slopes downwards, do not allow for vertical centering. Here's an image to showcase the problem .

绿色框中的字符基本上是完美的，因为它们没有向下的尾巴.红色框中的内容演示了该问题.

The characters in the green box are basically perfect, as they have no downward tail. Those in the red box demonstrate the problem.

我希望所有字符都垂直居中对齐.在图像中，尾巴向下的字符未垂直居中.这可以纠正吗?

I would like for all characters to be perfectly vertically centered. In the image, characters with a downward tail are not vertically centered. Is this possible to rectify?

这是小提琴，充分展示了问题所在.

.avatar {
    border-radius: 50%;
    display: inline-block;
    text-align: center;
    width: 125px;
    height: 125px;
    font-size: 60px;
    background-color: rgb(81, 75, 93);
    font-family: "Segoe UI";
    margin-bottom: 10px;
}

.character {
    position: relative;
    top: 50%;
    transform: translateY(-50%);
    line-height: 100%;
    color: #fff;
}

<div class="avatar">
  <div class="character">W</div>
</div>

<div class="avatar">
  <div class="character">y</div>
</div>

推荐答案

这是我使用JS的解决方案.想法是将元素转换为图像，以便以像素为单位获取其数据，然后遍历它们以查找每个字符的顶部和底部，并应用平移来固定对齐方式.这将与动态字体属性一起使用.

Here is my solution using JS. The idea is to transform the element into an image in order to get its data as pixel then loop through them to find the top and bottom of each character and apply a translation to fix the alignment. This will work with dynamic font properties.

代码没有经过优化，但突出了主要思想:

The code is not optimized but it highlight the main idea:

var elems = document.querySelectorAll(".avatar");

var fixes = [];


for (var i = 0; i < elems.length; i++) {
  var current = elems[i];
  domtoimage.toPixelData(current)
    .then(function(im) {
      /* Search for the top limit */
      var t = 0;
      for (var y = 0; y < current.scrollHeight; ++y) {
        for (var x = 0; x < current.scrollWidth; ++x) {
          var j = (4 * y * current.scrollHeight) + (4 * x);
          if (im[j] == 255 && im[j + 1] == 255 && im[j + 2] == 255) {
            t = y;
            break;
          }
        }
      }
      /* Search the bottom limit*/
      var b = 0;
      for (var y = (current.scrollHeight - 1); y >= 0; --y) {
        for (var x = (current.scrollWidth - 1); x >= 0; --x) {
          var j = (4 * y * current.scrollHeight) + (4 * x);
          if (im[j] == 255 && im[j + 1] == 255 && im[j + 2] == 255) {
            b = current.scrollHeight - y;
            break;
          }
        }
      }
      /* get the difference and apply a translation*/
      var diff = (b - t)/2;
      fixes.push(diff);
      /* we apply the translation when all are calculated*/
      if(fixes.length == elems.length) {
        for (var k = 0; k < elems.length; k++) {
          elems[k].querySelector('.character').style.transform = "translateY(" + fixes[k] + "px)";
        }
      }
    });
}

.avatar {
  border-radius: 50%;
  display: inline-flex;
  vertical-align:top;
  justify-content: center;
  align-items: center;
  width: 125px;
  height: 125px;
  font-size: 60px;
  background: 
    linear-gradient(red,red) center/100% 1px no-repeat,
    rgb(81, 75, 93);
  font-family: "Segoe UI";
  margin-bottom: 10px;
}

.character {
  color: #fff;
}

<script type="text/javascript" src="https://css-challenges.com/wp-content/themes/ronneby_child/js/dom-to-image.js"></script>
<div class="avatar">
  <div class="character">W</div>
</div>

<div class="avatar">
  <div class="character">y</div>
</div>

<div class="avatar">
  <div class="character" style="font-size:35px">a</div>
</div>

<div class="avatar">
  <div class="character" style="font-size:25px">2</div>
</div>
<div class="avatar">
  <div class="character">o</div>
</div>
<div class="avatar">
  <div class="character">|</div>
</div>
<div class="avatar">
  <div class="character">@</div>
</div>
<div class="avatar">
  <div class="character">Â</div>
</div>

<div class="avatar">
  <div class="character" style="font-family:arial">Q</div>
</div>
<div class="avatar">
  <div class="character">~</div>
</div>
<div class="avatar">
  <div class="character">8</div>
</div>

<div class="avatar">
  <div class="character">ä</div>
</div>
<div class="avatar">
  <div class="character">ç</div>
</div>

<div class="avatar">
  <div class="character">$</div>
</div>

<div class="avatar">
  <div class="character">></div>
</div>
<div class="avatar">
  <div class="character">%</div>
</div>

更新

这是代码的第一个优化:

Here is a first optimization of the code:

var elems = document.querySelectorAll(".avatar");
var k = 0;

for (var i = 0; i < elems.length; i++) {
  domtoimage.toPixelData(elems[i])
    .then(function(im) {
     var l = im.length;
      /* Search for the top limit */
      var t = 0;
      for (var j = 0; j < l; j+=4) {
          if (im[j+1] == 255) { /* Since we know the colors, we can only test the G composant */
            t = Math.ceil((j/4)/125);
            break;
          }
      }
      /* Search the bottom limit*/
      var b = 0;
      for (var j = l - 1; j >= 0; j-=4) {
          if (im[j+1] == 255) {
            b = 125 - Math.ceil((j/4)/125);
            break;
          }
      }
      /* get the difference and apply a translation*/
      elems[k].querySelector('.character').style.transform = "translateY(" + (b - t)/2 + "px)";
      k++;
    });
}

.avatar {
  border-radius: 50%;
  display: inline-flex;
  vertical-align:top;
  justify-content: center;
  align-items: center;
  width: 125px;
  height: 125px;
  font-size: 60px;
  background: 
    linear-gradient(red,red) center/100% 1px no-repeat,
    rgb(81, 75, 93);
  font-family: "Segoe UI";
  margin-bottom: 10px;
}

.character {
  color: #fff;
}

<script type="text/javascript" src="https://css-challenges.com/wp-content/themes/ronneby_child/js/dom-to-image.js"></script>
<div class="avatar">
  <div class="character">W</div>
</div>

<div class="avatar">
  <div class="character">y</div>
</div>

<div class="avatar">
  <div class="character" style="font-size:35px">a</div>
</div>

<div class="avatar">
  <div class="character" style="font-size:25px">2</div>
</div>
<div class="avatar">
  <div class="character">o</div>
</div>
<div class="avatar">
  <div class="character">|</div>
</div>
<div class="avatar">
  <div class="character">@</div>
</div>
<div class="avatar">
  <div class="character">Â</div>
</div>

<div class="avatar">
  <div class="character" style="font-family:arial">Q</div>
</div>
<div class="avatar">
  <div class="character">~</div>
</div>
<div class="avatar">
  <div class="character">8</div>
</div>

<div class="avatar">
  <div class="character">ä</div>
</div>
<div class="avatar">
  <div class="character">ç</div>
</div>

<div class="avatar">
  <div class="character">$</div>
</div>

<div class="avatar">
  <div class="character">></div>
</div>
<div class="avatar">
  <div class="character">%</div>
</div>

_{我为此使用了 dom-to-image 插件.}

_{I am using dom-to-image plugin for this.}

这篇关于如何在CSS中垂直对齐所有文本?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！