如何使用js來實現多行溢出隱藏功能

//調用方式:k('#p').ellipsistoText(3), k('#p').ellipsistoLine(2), k('#p').restoretoLine(), k('#p').restoretoText()
(function () {
 var k = function (selector) {
 return new F(selector)
 }
 var F = function (selector) {
 this.ele = document.querySelector(selector);
 if (!this.ele.ori_height) {
 this.ele.ori_height = this.ele.offsetHeight; //用于保存原始高度
 }
 if (!this.ele.ori_html) {
 this.ele.ori_html = this.ele.innerHTML; //用于保存原始內容
 }
 }
 F.prototype = {
 init: function () {
 this.ele.style.height = this.ele.ori_height;
 this.ele.innerHTML = this.ele.ori_html;
 },
 ellipsistoLine: function (l) {
 this.init();
 this.ele.style.cssText = 'overflow: hidden; height: ' + parseInt(window.getComputedStyle(this.ele)['line-height']) * l + 'px';
 },
 ellipsistoText: function (t) {
 this.init();
 var len = (this.ele.ori_html).length * (1/t);
 this.ele.innerHTML = this.ele.ori_html.substr(0, len);
 },
 restoretoLine: function () {
 this.ele.style.height = this.ele.ori_height + 'px';
 },
 restoretoText: function () {
 this.ele.innerHTML = this.ele.ori_html;
 }
 }
 window.k = k;
})(window)