var currentPage = 0; const totalHtmlFiles = 14; function changePublication() { if (currentPage >= 0 && currentPage < totalHtmlFiles) { var currentPageUrl = document.getElementById("contentIFrame").src; currentPageUrl = currentPageUrl.substring(0, currentPageUrl.lastIndexOf("/") + 1); var nextPageUrl = currentPageUrl; if (currentPage !== 0) currentPageUrl = currentPageUrl + "publication-" + currentPage + ".html"; else currentPageUrl = currentPageUrl + "publication" + ".html"; document.getElementById("contentIFrame").src = currentPageUrl; if ((currentPage + 1) < totalHtmlFiles) { nextPageUrl = nextPageUrl + "publication-" + (currentPage + 1) + ".html"; document.getElementById("dummyIFrame").src = nextPageUrl; } } } function showNextPage() { ++currentPage; changePublication(); showHideArrows(); } function showPreviousPage() { --currentPage; changePublication(); showHideArrows(); } function showHideArrows() { if (currentPage === 0) { document.getElementsByClassName("prev")[0].style.visibility = "hidden"; } else { document.getElementsByClassName("prev")[0].style.visibility = "visible"; } if (currentPage === (totalHtmlFiles -1)) { document.getElementsByClassName("next")[0].style.visibility = "hidden"; } else { document.getElementsByClassName("next")[0].style.visibility = "visible"; } }