一、单行省略方案：
一、WebKit浏览器或移动端的页面：
选择器 { display:block;/*行内元素需加*/ word-break:keep-all;/* 不换行，二选一*/ white-space:nowrap;/* 不换行 ，二选一*/ overflow:hidden;/* 内容超出宽度时隐藏超出部分的内容 */ text-overflow:ellipsis;/* 当对象内文本溢出时显示省略标记(...) ；需与overflow:hidden;一起使用。*/ }
二、多行省略方案
一、-webkit-line-clam;
<!DOCTYPE HTML> <html> <head> <meta charset="utf-8"> <title>无标题文档</title> </head> <body> <p style=" overflow : hidden; text-overflow: ellipsis; display: -webkit-box;//必须有 -webkit-line-clamp: 2; -webkit-box-orient: vertical;//必须有 "> static：对象遵循常规流。top，right，bottom，left等属性不会被应用。 relative： 对象遵循常规流，并且参照自身在常规流中的位置通过top，right，bottom，left属性进行偏移时不影响常规流中的任何元素。 absolute：对象脱离常规流，使用top，right，bottom，left等属性进行绝对定位，盒子的偏移位置不影响常规流中的任何元素，其margin不与其他任何margin折叠。fixed：对象脱离常规流，使用top，right，bottom，left等属性以窗口为参考点进行定位，当出现滚动条时，对象不会随着滚动。center：对象脱离常规流，使用top，right，bottom，left等属性指定盒子的位置或尺寸大小。盒子在其包含容器垂直水平居中。盒子的偏移位置不影响常规流中的任何元素，其margin不与其他任何margin折叠。（CSS3）page：盒子的位置计算参照absolute。盒子在分页媒体或者区域块内，盒子的包含块始终是初始包含块，否则取决于每个absolute模式。（CSS3） sticky： 对象在常态时遵循常规流。它就像是 relative 和 fixed 的合体，当在屏幕中时按常规流排版，当卷动到屏幕外时则表现如fixed。该属性的表现是现实中你见到的吸附效果。（CSS3）* CSS3新增属性可能存在描述错误及变更，仅供参考，持续更新 </p> </body> </html>
二、content:"...";
跨浏览器兼容：但是此方案有一个缺点：即使没有溢出是省略号也存在。
p { position:relative; line-height:1.4em; /* 3 times the line-height to show 3 lines */ height:4.2em; overflow:hidden; } p::after { content:"..."; font-weight:bold; position:absolute; bottom:0; right:0; padding:0 20px 1px 45px; background:url(http://css88.b0.upaiyun.com/css88/2014/09/ellipsis_bg.png) repeat-y; }
三、js解决方案：
一、js的解决方案：
clamp.js
/*! * Clamp.js 0.5.1 * * Copyright 2011-2013, Joseph Schmitt http://joe.sh * Released under the WTFPL license * http://sam.zoy.org/wtfpl/ */ (function(){ /** * Clamps a text node. * @param {HTMLElement} element. Element containing the text node to clamp. * @param {Object} options. Options to pass to the clamper. */ function clamp(element, options) { options = options || {}; var self = this, win = window, opt = { clamp: options.clamp || 2,//行数 useNativeClamp: typeof(options.useNativeClamp) != 'undefined' ? options.useNativeClamp : true,//是否使用-webkit-line-clamp属性,默认是true splitOnChars: options.splitOnChars || ['.', '-', '–', '—', ' '], //Split on sentences (periods), hypens, en-dashes, em-dashes, and words (spaces). animate: options.animate || false,//是否实现动画折叠,默认是无动画 truncationChar: options.truncationChar || '…',//省略的符号（不限于省略号） truncationHTML: options.truncationHTML//省略的内容（不限于符号） }, sty = element.style, originalText = element.innerHTML, supportsNativeClamp = typeof(element.style.webkitLineClamp) != 'undefined', clampValue = opt.clamp, isCSSValue = clampValue.indexOf && (clampValue.indexOf('px') > -1 || clampValue.indexOf('em') > -1), truncationHTMLContainer; if (opt.truncationHTML) { truncationHTMLContainer = document.createElement('span'); truncationHTMLContainer.innerHTML = opt.truncationHTML; } // UTILITY FUNCTIONS __________________________________________________________ /** * Return the current style for an element. * @param {HTMLElement} elem The element to compute. * @param {string} prop The style property. * @returns {number} */ function computeStyle(elem, prop) { if (!win.getComputedStyle) { win.getComputedStyle = function(el, pseudo) { this.el = el; this.getPropertyValue = function(prop) { var re = /(-([a-z]){1})/g; if (prop == 'float') prop = 'styleFloat'; if (re.test(prop)) { prop = prop.replace(re, function () { return arguments[2].toUpperCase(); }); } return el.currentStyle && el.currentStyle[prop] ? el.currentStyle[prop] : null; } return this; } } return win.getComputedStyle(elem, null).getPropertyValue(prop); } /** * Returns the maximum number of lines of text that should be rendered based * on the current height of the element and the line-height of the text. */ function getMaxLines(height) { var availHeight = height || element.clientHeight, lineHeight = getLineHeight(element); return Math.max(Math.floor(availHeight/lineHeight), 0); } /** * Returns the maximum height a given element should have based on the line- * height of the text and the given clamp value. */ function getMaxHeight(clmp) { var lineHeight = getLineHeight(element); return lineHeight * clmp; } /** * Returns the line-height of an element as an integer. */ function getLineHeight(elem) { var lh = computeStyle(elem, 'line-height'); if (lh == 'normal') { // Normal line heights vary from browser to browser. The spec recommends // a value between 1.0 and 1.2 of the font size. Using 1.1 to split the diff. lh = parseInt(computeStyle(elem, 'font-size')) * 1.2; } return parseInt(lh); } // MEAT AND POTATOES (MMMM, POTATOES...) ______________________________________ var splitOnChars = opt.splitOnChars.slice(0), splitChar = splitOnChars[0], chunks, lastChunk; /** * Gets an element's last child. That may be another node or a node's contents. */ function getLastChild(elem) { //Current element has children, need to go deeper and get last child as a text node if (elem.lastChild.children && elem.lastChild.children.length > 0) { return getLastChild(Array.prototype.slice.call(elem.children).pop()); } //This is the absolute last child, a text node, but something's wrong with it. Remove it and keep trying else if (!elem.lastChild || !elem.lastChild.nodeValue || elem.lastChild.nodeValue == '' || elem.lastChild.nodeValue == opt.truncationChar) { elem.lastChild.parentNode.removeChild(elem.lastChild); return getLastChild(element); } //This is the last child we want, return it else { return elem.lastChild; } } /** * Removes one character at a time from the text until its width or * height is beneath the passed-in max param. */ function truncate(target, maxHeight) { if (!maxHeight) {return;} /** * Resets global variables. */ function reset() { splitOnChars = opt.splitOnChars.slice(0); splitChar = splitOnChars[0]; chunks = null; lastChunk = null; } var nodeValue = target.nodeValue.replace(opt.truncationChar, ''); //Grab the next chunks if (!chunks) { //If there are more characters to try, grab the next one if (splitOnChars.length > 0) { splitChar = splitOnChars.shift(); } //No characters to chunk by. Go character-by-character else { splitChar = ''; } chunks = nodeValue.split(splitChar); } //If there are chunks left to remove, remove the last one and see if // the nodeValue fits. if (chunks.length > 1) { // console.log('chunks', chunks); lastChunk = chunks.pop(); // console.log('lastChunk', lastChunk); applyEllipsis(target, chunks.join(splitChar)); } //No more chunks can be removed using this character else { chunks = null; } //Insert the custom HTML before the truncation character if (truncationHTMLContainer) { target.nodeValue = target.nodeValue.replace(opt.truncationChar, ''); element.innerHTML = target.nodeValue + ' ' + truncationHTMLContainer.innerHTML + opt.truncationChar; } //Search produced valid chunks if (chunks) { //It fits if (element.clientHeight <= maxHeight) { //There's still more characters to try splitting on, not quite done yet if (splitOnChars.length >= 0 && splitChar != '') { applyEllipsis(target, chunks.join(splitChar) + splitChar + lastChunk); chunks = null; } //Finished! else { return element.innerHTML; } } } //No valid chunks produced else { //No valid chunks even when splitting by letter, time to move //on to the next node if (splitChar == '') { applyEllipsis(target, ''); target = getLastChild(element); reset(); } } //If you get here it means still too big, let's keep truncating if (opt.animate) { setTimeout(function() { truncate(target, maxHeight); }, opt.animate === true ? 10 : opt.animate); } else { return truncate(target, maxHeight); } } function applyEllipsis(elem, str) { elem.nodeValue = str + opt.truncationChar; } // CONSTRUCTOR ________________________________________________________________ if (clampValue == 'auto') { clampValue = getMaxLines(); } else if (isCSSValue) { clampValue = getMaxLines(parseInt(clampValue)); } var clampedText; if (supportsNativeClamp && opt.useNativeClamp) { sty.overflow = 'hidden'; sty.textOverflow = 'ellipsis'; sty.webkitBoxOrient = 'vertical'; sty.display = '-webkit-box'; sty.webkitLineClamp = clampValue; if (isCSSValue) { sty.height = opt.clamp + 'px'; } } else { var height = getMaxHeight(clampValue); if (height <= element.clientHeight) { clampedText = truncate(getLastChild(element), height); } } return { 'original': originalText, 'clamped': clampedText } } window.$clamp = clamp; })();
引用：
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Clamp.js Example 1</title> </head> <body> <style> #chuli { width: 300px; background:green; font-size:16px; line-height:36px;/*必须设置*/ } </style> <div> <p id="chuli"> euismod posuere et id sapien. Cras ligula leo, hendrerit vitae sagittis nec, commodo sed lacus. In aliquam pretium mauris sed ullamcorper. Phasellus fermentum iaculis massa ac condimentum. Ut nisl turpis, vulputate in rhoncus sed,</p> <ul><li>elementum eget</li><li>massa. Sed a diam</li><li>dui, in <a href="#">iaculis felis.</a></li></ul> </div> <script src="../clamp.js"></script> <script> var chuli = document.getElementById("chuli"); $clamp(chuli, {clamp: 4, useNativeClamp: false}); </script> </body> </html>
注意：用这个方法，一定要给文字加行高。
四、jq的dotdotdot.js
http://dotdotdot.frebsite.nl