/*** >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>*                分页组件* >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>*/let pagehelper = {/*** 跳转到哪一页*/goto_page: function (page) {let pmax = parseInt($("#pmax").val())if (page < 1 || page > pmax) {layer.msg('无效页码');// alert('页码超出范围');return;}$("#p").val(page)console.log('跳转到第' + page + '页');// 更新按钮pagehelper.updateButtons();cms.reload();},/*** 点击上一页*/goto_previous: function () {let p = parseInt($("#p").val())if (p > 1) {pagehelper.goto_page(p - 1);}},/*** 点击下一页*/goto_next: function () {let p = parseInt($("#p").val())let pmax = parseInt($("#pmax").val())if (p < pmax) {pagehelper.goto_page(p + 1);}},/*** 生成五个页码*/generatePageNumbers: function (currentPage, totalPages) {// 计算要显示的页码范围let minPage = Math.max(1, currentPage - 2); // 至少从1开始let maxPage = Math.min(totalPages, currentPage + 2); // 最多到总页数// 如果总页数小于等于5，直接显示全部页码// if (totalPages <= 5) {//     minPage = 1;//     maxPage = totalPages;// }// 如果总页数允许且当前页接近两端，则调整最小或最大页码以包含足够的页码// 特别是当当前页是前几页或后几页时if (currentPage <= 3 && totalPages > 5) {maxPage = Math.min(totalPages, 5); // 确保不超过总页数} else if (currentPage >= totalPages - 2 && totalPages > 5) {minPage = Math.max(1, totalPages - 4); // 确保不小于1}// 生成页码数组let pageNumbers = [];for (let i = minPage; i <= maxPage; i++) {pageNumbers.push(i);}return pageNumbers;},/*** 重绘分页组件*/updateButtons: function () {let p = parseInt($("#p").val())let pmax = parseInt($("#pmax").val())var nav = document.getElementById('nav');nav.innerHTML = ''; // 清空nav的内容// 创建上一页按钮var prevButton = document.createElement('button');prevButton.onclick = function () {pagehelper.goto_previous();};prevButton.textContent = '上一页';if (p == 1) {// 如果当前是第一页，则不显示prevButton.style.display = 'none';}//创建五个页码let pages = pagehelper.generatePageNumbers(p, pmax);// 创建页码按钮var ul = document.createElement('ul');for (var i = 0; i < pages.length; i++) {var pageNum = pages[i];var li = document.createElement('li');var pageButton = document.createElement('button');pageButton.onclick = function (page) {return function () {pagehelper.goto_page(page);};}(pageNum); // 闭包确保正确的页码被传递pageButton.textContent = pageNum;if (pageNum == p) {// 如果不是当前页，则禁用pageButton.disabled = true;}li.appendChild(pageButton);ul.appendChild(li);}// 创建跳转输入框和下一页按钮var input = document.createElement('input');input.type = 'number';input.name = 'manual';input.placeholder = '最大页' + pmax;// 设置事件监听器input.onkeydown = function (event) {if (event.keyCode === 13) { // 只在按下回车键时验证let toPage = parseInt(this.value, 10);if (!isNaN(toPage) && toPage > 0 && toPage <= pmax) {pagehelper.goto_page(toPage);} else {pagehelper.goto_page(pmax);}}};var nextButton = document.createElement('button');nextButton.onclick = function () {pagehelper.goto_next();};nextButton.textContent = '下一页';nextButton.style.display = p < pmax ? '' : 'none'; // 如果当前是最后一页，则不显示// 将元素添加到nav中nav.appendChild(prevButton);nav.appendChild(ul);nav.appendChild(input);nav.appendChild(nextButton);}};/*** >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>*                分页组件* >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>*/