//-------------------------------效果制作------------------------------------

//幻灯片切换代码
function slideBox(sel) {
    var index = 1;
    var sum = $(sel + " .hd ul li").length;
    set_css(sel + " .hd ul li", sel + " .hd ul li:first-child", "on");
    set_vis(sel + " .bd ul li", sel + " .bd ul li:first-child");

    $(sel + " .hd ul li").each(function (i) {
        $(this).mouseover(function () {
            set_css(sel + " .hd ul li", sel + " .hd ul li:nth-child(" + (i + 1) + ")", "on");
            set_vis(sel + " .bd ul li", sel + " .bd ul li:nth-child(" + (i + 1) + ")");
            index = $(sel + " .hd ul li").index($(sel + " .hd ul li.on"));
        });
    });

    $(sel + " .prev").click(function () {
        --index;
        a();
    });
    $(sel + " .next").click(function () {
        ++index;
        a();
    });

    var int = window.setInterval(b, 5000);
    $(sel).hover(
        function () {
            window.clearInterval(int);
        },
        function () {
            int = window.setInterval(b, 5000);
        }
    );
    function b() {
        index++;
        a();
    }

    function a() {
        (index <= 0) ? index = sum : null;
        (index >= (sum + 1)) ? index = 1 : null;
        set_css(sel + " .hd ul li", sel + " .hd ul li:nth-child(" + (index) + ")", "on");
        set_vis(sel + " .bd ul li", sel + " .bd ul li:nth-child(" + (index) + ")");
    }
}

//-------------------------------通用函数------------------------------------
//集合中设置一项的css
function set_css(sel, theone, value) {
    $(sel).each(function () {
        $(this).attr("class", "");
    });
    $(theone).attr("class", value);
}

//集合中设置一项的style
function set_vis(sel, theone) {
    $(sel).each(function () {
        $(this).css("display", 'none');
    });
    $(theone).css("display", 'block');
}