@writ/utils/showpager.js

My tool kit

'use strict';

/**
 * 分页函数
 * @param {*} thisPage 
 * @param {*} pageCount 
 * @param {*} href 
 * @param {*} htmlpre 
 * @param {*} limitNum 
 */
function showpager(thisPage, pageCount, href, htmlpre, limitNum) {
    limitNum = limitNum || 5;
    thisPage = utils.toInt(thisPage);
    pageCount = utils.toInt(pageCount);
    href = href || '';

    // 链接格式，首页链接
    let hrefformat,
        firstpage = href.replace(/_p(\d+|all)\.html/gi, '.html').replace('index.html', '');

    // 首页url为/结尾的情况
    if (!firstpage) {
        firstpage = './';
    }

    if (/_p(\d+|all)\.html/gi.test(href)) {
        hrefformat = href.replace(/_p(\d+|all)\.html/gi, '_p{0}.html');
    } else if (href.indexOf('.html') != -1) {
        hrefformat = href.replace('.html', '_p{0}.html');
    } else {
        hrefformat = 'index_p{0}.html';
    }

    const getHref = function (page) {
        return page == 1 ? firstpage : hrefformat.format(page);
    };

    const comparePage = function (thispage, p) {
        let str = '';

        if (thisPage !== p) {
            if (p === 1 && thisPage <= 1) {
                str += `<span class="active">${p}</span>`;
            } else {
                str += `<a href="${getHref(p)}">${p}</a>`;
            }
        } else {
            str += `<span class="active">${p}</span>`;
        }

        return str;
    };

    let str = htmlpre || '';
    let p = 1;

    if (thisPage > 1) {
        str += `<a class="prev" href="${getHref(thisPage - 1)}"><i class="ift-prev"></i></a>`;
    } else {
        str += '<span class="prev"><i class="ift-prev"></i></span>';
    }

    if (pageCount < limitNum * 2) {
        for (p = 1; p <= pageCount; p++) {
            str += comparePage(thisPage, p);
        }
    } else {
        str += comparePage(thisPage, 1);

        if (thisPage <= limitNum) {
            for (p = 2; p <= limitNum + 2; p++) {
                str += comparePage(thisPage, p);
            }
            str += '…';
        } else {
            str += '…';
            if (thisPage <= pageCount - limitNum) {
                for (p = thisPage - 2; p <= thisPage + 2; p++) {
                    str += comparePage(thisPage, p);
                }
            } else {
                for (p = pageCount - (limitNum + 1); p <= pageCount - 1; p++) {
                    str += comparePage(thisPage, p);
                }
            }
            if (thisPage + Math.ceil(limitNum / 2) < pageCount - 1) {
                str += '…';
            }
        }
        str += comparePage(thisPage, pageCount);
    }

    if (thisPage < pageCount) {
        str += `<a class="next" href="${getHref(thisPage + 1)}"><i class="ift-next"></i></a>`;
    } else {
        str += '<span class="next"><i class="ift-next"></i></span>';
    }

    return str;
}

module.exports = showpager;