时间：2020-01-16 14:35:39 | 栏目： | 点击：次
但有个问题，如果没有针对一个元素设置 line-height 值，则其默认值为 normal ，这个值在桌面浏览器中通常是 1.2 ，但还与字体有关。因此，最好是对需要计算行数的元素设置一下 line-height 值。
一个简单的实现如下：
function countLines(ele) {
var styles = window.getComputedStyle(ele, null);
var lh = parseInt(styles.lineHeight, 10);
var h = parseInt(styles.height, 10);
var lc = Math.round(h / lh);
console.log('line count:', lc, 'line-height:', lh, 'height:', h);
return lc;
}
完整代码示例：
<!DOCTYPE html>
<html>
<head>
<title>Line Count</title>
<style type="text/css">
p {
line-height: 1.3em;
}
</style>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312"></head>
<body>
<p id="target">She just made having a baby look lovely. Everything is white and she always has a fresh blueberry pie that's steaming and scones and clotted cream and she's reading The Old Man and the Sea and her little boy is rolly with bonnets. It's amazing, and I thought this is lovely. My kid is like playing with like explosive devices. I don't know where she's found them, like sticking them in our dog's ear. She already knows how to dry wall cause she puts holes in the wall.<br />
“今天的中国人一如当年的德国人，沉迷于‘崛起'幻觉，习惯于听信他人的吹捧，还想当然地认为只要中国继续保持经济增长，不仅未来的经济总量超越‘世界老大'美国可以期待，中国实现全面复兴也将是囊中之物。”上海外国语大学国际关系与公共事务学院教授程亚文在其新著《大国战略力》中尖锐地指出中国现下有不少人陷入了“盛世”幻觉，并没有意识到在经济总量的背后，中国其实还是一个极为落后的国家。世界上还没有一个大国是在风平浪静中兴起的，中国的新一轮文明复兴也将充满风险和曲折。防止国家崩溃、解体或衰败应该成为中国国家战略的重中之重。染上“软乎乎的幸福主义”只会让一个国家变得脆弱。
</p>
<p>行数：<span id="shower"></span></p>
改变窗口大小，自动计算
<button onclick="countLines()">立刻计算</button>
<script type="text/javascript">
var target = document.getElementById('target');
var shower = document.getElementById('shower');
function countLines(ele) {
var styles = window.getComputedStyle(ele, null);
var lh = parseInt(styles.lineHeight, 10);
var h = parseInt(styles.height, 10);
var lc = Math.round(h / lh);
console.log('line count:', lc, 'line-height:', lh, 'height:', h);
return lc;
}
function change() {
shower.innerHTML = countLines(target);
}
window.onresize = change;
change();
</script>
</body>
</html>