js中日期转换为时间戳

function dateToTimestamp(date) {
               //方法一
        var newDate = new Date();
        newDate.setFullYear(date.substring(0,4));
        newDate.setMonth(date.substring(5,7)-1);
        console.log('3--' + date.substring(8,10));
        newDate.setDate(date.substring(8,10)); 
        newDate.setHours(date.substring(11,13)); 
        newDate.setMinutes(date.substring(14,16)); 
        newDate.setSeconds(date.substring(17,19));
        console.log('date',newDate);
        return Date.parse(newDate)/1000;
                //方法二
        date = date.replace(/-/g,'/'); // 将-替换成/，因为下面这个构造函数只支持/分隔的日期字符串
        date = new Date(date); // 构造一个日期型数据，值为传入的字符串
        var time = date.getTime();
        time = time / 1000;
        return time;
    }