js原型+jquery实现页码过多时显示省略号的分页器组件

// 定义分页器构造函数
function Pagination($container, options) {
    this.$container = $container;
    this.options = $.extend({}, Pagination.DEFAULTS, options);
    this.render();
    this.bindEvents();
}
 
// 默认参数
Pagination.DEFAULTS = {
    currentPage: 1,
    totalPages: 10,
    visiblePages: 5
};
 
// 渲染分页器
Pagination.prototype.render = function() {
    var html = this.getHtml();
    this.$container.html(html);
};
 
// 获取分页器HTML结构
Pagination.prototype.getHtml = function() {
    var html = '';
    var totalPages = this.options.totalPages;
    var currentPage = this.options.currentPage;
    var visiblePages = this.options.visiblePages;
    var startPage, endPage;
 
    if (totalPages <= visiblePages) {
        startPage = 1;
        endPage = totalPages;
    } else {
        // 计算开始和结束页码
        var middle = Math.floor(visiblePages / 2);
        startPage = currentPage - middle;
        endPage = currentPage + visiblePages - middle - 1;
 
        // 如果开始页码小于1，则向后移动
        if (startPage < 1) {
            endPage = endPage - (1 - startPage);
            startPage = 1;
        }
        // 如果结束页码大于总页数，则向前移动
        if (endPage > totalPages) {
            startPage = startPage - (endPage - totalPages);
            endPage = totalPages;
        }
    }
 
    // 添加首页和前一页的按钮
    html += '<a href="?page=1" class="first-page' + (currentPage === 1 ? ' disabled' : '') + '">首页</a>';
    html += '<a href="?page=' + (currentPage - 1) + '" class="prev-page' + (currentPage === 1 ? ' disabled' : '') + '">&laquo;</a>';
 
    // 添加页码
    for (var i = startPage; i <= endPage; i++) {
        html += '<a href="?page=' + i + '" class="page-number' + (i === currentPage ? ' active' : '') + '">' + i + '</a>';
    }
 
    // 添加后一页和末页按钮
    html += '<a href="?page=' + (currentPage + 1) + '" class="next-page' + (currentPage === totalPages ? ' disabled' : '') + '">&raquo;</a>';
    html += '<a href="?page=' + totalPages + '" class="last-page' + (currentPage === totalPages ? ' disabled' : '') + '">末页</a>';
 
    return html;
};
 
// 绑定分页器事件
Pagination.prototype.bindEvents = function() {
    var that = this;
    this.$container.on('click', '.page-number, .first-page, .last-page, .prev-page, .next-page', function(e) {
        e.preventDefault();
        var $this = $(this);
        if (!$this.hasClass('disabled')) {
            var page = $this.attr('