js返回上一级页面,返回上一级页面快捷键

var historyUtils = { add : function (url) { var historyArray = historyUtils.getLocal(); if (!historyArray) { historyArray = []; } var currentPage = historyArray.pop(); if (currentPage && currentPage == url) { //do nothing } else if (currentPage){ historyArray.push(currentPage); //历史里面没有现在传入的url，在加回去 } historyArray.push(url); historyUtils.saveLocal(historyArray); }, back : function() { var historyArray = historyUtils.getLocal(); var currentPage = historyArray.pop();//去掉当前页面，pop取最后，类似stack var history = historyArray.pop(); if (!history) {//没有历史页面 historyUtils.add(currentPage);//将当前页面加入回数组中 return; } historyUtils.saveLocal(historyArray); window.location.href = history; }, getLocal : function() { var result = window.sessionStorage.getItem(historyUtils.key); if (!result) { return null; } return JSON.parse(result); }, saveLocal : function(data) { window.sessionStorage.setItem(historyUtils.key, JSON.stringify(data)); }, init : function() { historyUtils.saveLocal([]); }, key : "_history_"};historyUtils.add(window.location.href);