代码是这样的，获取某一个文件目录：

getToc: function(dir, callback){
    //console.log(dir)
    var resJSON = {
        queryDir: dir,
        folder: [],
        document: []
    };
    fs.readdir(dir, function(err, files){
        if(err){
            resJSON.err = err;
            callback(resJSON);
            return;
        }
        for(var i = 0, len = files.length; i < len; i++){
            var pathname = dir + "\/" + files[i];
            var stat = fs.lstatSync(pathname);
            if (!stat.isDirectory()){
                var a = files[i].split('.');
                var date = new Date(stat.atime).toLocaleFormat();  //这行报错
                resJSON.document.push({type:a[a.length-1],name:files[i],size:stat.size,lastModfied:date});
            } else {
                resJSON.folder.push(files[i]);
            }
        }
        callback(resJSON);
    });
}

错误提示是没有toLocaleFormat方法：TypeError: Object Mon Jan 28 2013 20:20:33 GMT+0800 (CST) has no method 'toLocaleFormat’ 在客户端下面代码能正确输出时间格式的： 为什么服务端这个方法不存在呢？