按数组对对象数组进行排序

Question

I have an array of objects like so;

var orders = [
  {
    status: "pending"
  },
  {
    status: "received"
  },
  {
    status: "sent"
  },
  {
    status: "pending"
  }
]

I want to sort this array of objects based on the value of the status key, but so that the order of the objects matches the order of the array of the possible values of the status key;

var statuses = ["pending", "sent", "received"]

Therefore, after sorting, the two "pending" objects would be first, followed by the "sent" object, and finally the "received" object.

How can I do this?

Answer 1

You can do this with sort() and indexOf() .

 var orders = [{ status: "pending" }, { status: "received" }, { status: "sent" }, { status: "pending" }] var statuses = ["pending", "sent", "received"] var result = orders.sort(function(a, b) { return statuses.indexOf(a.status) - statuses.indexOf(b.status) }) console.log(result) 

Answer 2

You can use the sort() function:

 var statuses = ["pending", "sent", "received"]; var orders = [ { status: "pending" }, { status: "received" }, { status: "sent" }, { status: "pending" } ]; orders.sort(function(a, b) { return statuses.indexOf(a.status) - statuses.indexOf(b.status); }); console.log(orders); 

Answer 3

Use Array#sort method to sort the array of objects. Where use an object to store the index of keys which helps to avoid using Array#indexOf method(which is slower).

 var orders = [{ status: "pending" }, { status: "received" }, { status: "sent" }, { status: "pending" }]; var statuses = ["pending", "sent", "received"]; // generate the object which holds the index in array // or use an object instead of array which holds the index var index = statuses.reduce(function(obj, k, i) { obj[k] = i; return obj; }, {}) console.log( orders.sort(function(a, b) { return index[a.status] - index[b.status]; }) ) 

Answer 4

You could use an object as hash table for the sort order.

 var orders = [{ status: "pending" }, { status: "received" }, { status: "sent" }, { status: "pending" }], statuses = { pending: 1, sent: 2, received: 3 }; orders.sort(function (a, b) { return statuses[a.status] - statuses[b.status]; }); console.log(orders); 

Answer 5

Can use methods like indexOf() within sort callback but more efficient is to build hashmap of the indices first

var statIndex = statuses.reduce(function(a,c,i){
   a[c] = i;
   return a
},{})

orders.sort(function(a,b){
   return statIndex[a.status] - statIndex[b.status]
})