javascript - 从数组中删除无效键，并以最高值进行排序和限制

Question

如何从数组中删除这样的条目

• _id=0
• _id = ""
• _id = 未定义
• _id = null

然后排序并将输出限制为仅 7 个成本最高的项目？

MyArray

[
{_id : "" , M : "4", S : "2", Costs: "6"},
{_id : "0", M : "1", S : "0", Costs: "1"},
{_id : "1", M : "1", S : "0", Costs: "1"},
{_id : "2", M : "1", S : "0", Costs: "1"},
{_id : "3", M : "0", S : "3", Costs: "3"},
{_id : "4",  M : "1", S : "0", Costs: "1"},
{_id : "5",  M : "1", S : "0", Costs: "5"},
{_id : "6",  M : "1", S : "0", Costs: "2"},
{_id : "7",  M : "1", S : "0", Costs: "5"},
{_id : "8",  M : "1", S : "0", Costs: "1"},
{_id : "9",  M : "1", S : "0", Costs: "10"}
]

DESIRED OUTPUT

[
{_id : "9",  M : "1", S : "0", Costs: "10"},
{_id : "7",  M : "1", S : "0", Costs: "5"},
{_id : "5",  M : "1", S : "0", Costs: "5"},
{_id : "3", M : "0", S : "3", Costs: "3"},
{_id : "6",  M : "1", S : "0", Costs: "2"},
{_id : "1", M : "1", S : "0", Costs: "1"},
{_id : "2", M : "1", S : "0", Costs: "1"}
]

Answer 1

你可以filter然后sort然后slice将它们链接如下。

var result = arr.filter(function(doc){
    return !!parseInt(doc._id);
}).sort(function(a,b){
    return (parseInt(b.Costs) - parseInt(a.Costs));
}).slice(0,7);