Node + Mongo Native：通過排序生成請求

Question

我正在爲MongoDB創建分步請求。一切正常，但排序選項不能被Mongo識別。我做錯了什麼？

var request = {} 
    request['show'] = 1; 
    request['category'] = category; 
    switch (sort) { 
     case "new_first": 
      request['sort'] = "[['time_added', -1]]"; 
      break; 
     case "old_first": 
      request['sort'] = "[['time_added', 1]]"; 
      break; 
    } 
collection.find(request, function(err, posts) { 
....  

謝謝！

Answer 1

找到了解決辦法：

sort_query = JSON.parse('{"sort":[["time_added",-1]]}') 

它的工作！