jquery获取当前日期的前一天

代码如下所示，有其他需求，请酌情修改
var default_time = toLongDate(new Date().getTime()-86400000);

function toLongDate(m) {
    var date = new Date(m);
    return date.getFullYear() + "-" + (date.getMonth() + 1 < 10 ? "0" + (date.getMonth() + 1) : date.getMonth() + 1) + "-" + (date.getDate() < 10 ? "0" + date.getDate() : date.getDate());//+" "+date.getHours()+":"+date.getMinutes()+":"+date.getSeconds();
}