function displaySubMenu(li) { 
var subMenu = li.getElementsByTagName("ul")[0]; 
subMenu.style.display = "block"; 
} 
function hideSubMenu(li) { 
var subMenu = li.getElementsByTagName("ul")[0]; 
subMenu.style.display = "none"; 
} 
<!-- 加入收藏代码 Start -->
function AddFavorite(sURL, sTitle) { 
    try { 
        window.external.addFavorite(sURL, sTitle); 
    } catch (e) { 
        try { 
            window.sidebar.addPanel(sTitle, sURL, ""); 
        } catch (e) { 
            alert("加入收藏失败,请手动添加."); 
        } 
    } 
} 
<!-- 加入收藏代码 End -->
<!-- 设为首页代码 Start -->
function setHomepage(pageURL) { 
    if (document.all) { 
        document.body.style.behavior='url(#default#homepage)'; 
        document.body.setHomePage(pageURL); 
    } 
    else if (window.sidebar) { 
        if(window.netscape) { 
            try { 
                netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect"); 
            } 
            catch (e) { 
                alert( "该操作被浏览器拒绝，如果想启用该功能，请在地址栏内输入 about:config,然后将项signed.applets.codebase_principal_support 值该为true" ); 
            } 
        } 
        var prefs = Components.classes['@mozilla.org/preferences-service;1'].getService(Components. interfaces.nsIPrefBranch); 
        prefs.setCharPref('browser.startup.homepage',pageURL); 
    } 
}
<!-- 设为首页代码 End -->