//浮动提示框 1秒后消失
toast(msg, isError, sec) {
    var div = $(‘#toast‘);
    div.html(msg);
    div.css({visibility: ‘hidden‘});
    if (isError) {
        div.addClass("error");
    } else {
        div.removeClass("error");
    }
    var top = ($(window).height() - div.height()) / 2;
    var left = ($(window).width() - (div.width() || 80)) / 2;
    var scrollTop = $(document).scrollTop();
    var scrollLeft = $(document).scrollLeft();
    div.css({position: ‘absolute‘, ‘top‘: top + scrollTop, left: left + scrollLeft, visibility: ‘‘}).show();
    //1秒后隐藏
    var sec = sec || 3000;
    div.delay(sec).hide(0);
},

toast, 警告窗