var obj = document.getElementById("frameContent");  //获取内容层
var pages = document.getElementById("pages");         //获取翻页层
var pgindex = 1;
var allpages = 0;                                       //当前页
window.onload = function()                             //重写窗体加载的事件
{
    allpages = Math.ceil(parseInt(obj.scrollHeight) / parseInt(obj.offsetHeight)); //获取页面数量
    outPageNum(pgindex);
}
function gotopage(value) {
    try {
        value == "-1" ? showPage(pgindex - 1) : showPage(pgindex + 1);
    } catch (e) {

    }
}


//根据高度，输出指定的页
function showPage(pageINdex) {
    pageINdex = parseInt(pageINdex);
    if (pageINdex >= 1 && pageINdex <= allpages) {
        obj.scrollTop = (pageINdex - 1) * parseInt(obj.offsetHeight);
        pgindex = pageINdex;
        outPageNum(pgindex);
    }
}


//输出页码
function outPageNum(pageINdex) {

    pages.innerHTML = "<b>共" + allpages + "页</b>";     //输出页面数量

    for (var i = 1; i <= allpages; i++) {
        if (i == pageINdex) {
            pages.innerHTML += "<span style='font-weight: bold; color: #38a786'>" + i + "</span>"; //循环输出第几页
        }
        else {
            pages.innerHTML += "<a href=\"javascript:showPage('" + i + "');\">[" + i + "]</a> "; //循环输出第几页
        }
    }

    if (pageINdex > 1 && pageINdex < allpages) {
        pages.innerHTML += " <a href=\"javascript:gotopage('-1');\">上一页</a>  <a href=\"javascript:gotopage('1');\">下一页</a>";
    }
    else if (pageINdex == 1 && pageINdex < allpages) {
        pages.innerHTML += "<a href=\"javascript:gotopage('1');\">下一页</a>";
    }
    else if (pageINdex == allpages && pageINdex > 1) {
        pages.innerHTML += "<a href=\"javascript:gotopage('-1');\">上一页</a> ";
    }

}