javascript - 如何获得按 "value"值降序排序的映射/归约结果？如果也使用列表函数可以实现这一点？

Question

我有这样的 View 和减少: map :

   function(doc) {
           if(doc.type){
            var usersLength = doc.users.length;
            for (var i = 0; i < usersLength ; i++) {
                    emit([doc.users[i].userid,doc.Service.ownId], 1);
                }
            }
        }

减少:

 function(keys, values, rereduce)
    {
      return sum(values);
    }

然后像这样调用 View :_design/aaa/_view/getUserId?group=true&group_level=2&startkey=["111111"]&endkey=["111111",{}]

我可以得到下面的结果集:

{"rows":[
{"key":["111111",""],"value":7},
{"key":["111111","FFFF26"],"value":1},
{"key":["111111","FFFF44"],"value":7},
{"key":["111111","FFFF34"],"value":2}
]}

但是，我希望将上面的结果集按照“value”值的降序排序。如果也使用列表功能可以实现吗？预期结果如下:

{"rows":[
{"key":["111111",""],"value":7},
{"key":["111111","FFFF44"],"value":7},
{"key":["111111","FFFF34"],"value":2},
{"key":["111111","FFFF26"],"value":1}
]}

Answer 1

如果您想对结果集进行排序，则必须按值降序排序，您可以使用比较器回调进行排序:

// ES6 Syntax
let originalResult = {
"rows":[
  {"key":["111111",""],"value":7},
  {"key":["111111","FFFF26"],"value":1},
  {"key":["111111","FFFF44"],"value":7},
  {"key":["111111","FFFF34"],"value":2}
]}

let newResult = {
  rows: originalResult.rows.sort((a, b) => b.value - a.value)
}