function timestampToTime(timestamp) {
    if (typeof(timestamp) == "undefined"){
        return ""
    }else{
        var date = new Date(timestamp * 1000);//时间戳为10位需*1000，时间戳为13位的话不需乘1000
        var Y = date.getFullYear() + '-';
        var M = (date.getMonth()+1 < 10 ? '0'+(date.getMonth()+1) : date.getMonth()+1) + '-';
        var D = (date.getDate() < 10 ? '0'+date.getDate() : date.getDate()) + ' ';
        return Y+M+D;
    }

}