用另一个数组对较大的javascript数组进行排序，然后将值移到该数组的顶部

Question

I apologize if this has been asked before but I was looking to sort a javascript array based on the criteria of another array. I know that all of the values contained in the criteria array will be in the larger array somewhere but I need the ones from the criteria array to be moved to the top of the list.

For example I have a larger array that looks something like this :

array = [
  {_id: "123", username: "username1",platform: "xbox"},
  {_id: "124", username: "username2",platform: "xbox"},
  {_id: "125", username: "username3",platform: "ps4"},
  {_id: "126", username: "username4",platform: "pc"},
  {_id: "127", username: "username5",platform: "ps4"},
  {_id: "128", username: "username6",platform: "pc"}
    ];

I then need to sort this larger array based on the criteria of the smaller array and then move those values to the top of the larger one

So in this case the criteria array would be

critarray = [
 {_id: "124", username: "username2",platform: "xbox"},
 {_id: "127", username: "username5",platform: "ps4"},
 {_id: "128", username: "username6",platform: "pc"},
];

The the larger array would be sorted as follows:

array = [
  {_id: "124", username: "username2",platform: "xbox"},
  {_id: "127", username: "username5",platform: "ps4"},
  {_id: "128", username: "username6",platform: "pc"},
  {_id: "123", username: "username1",platform: "xbox"},
  {_id: "125", username: "username3",platform: "ps4"},
  {_id: "126", username: "username4",platform: "pc"},
    ];

Also it doesn't really matter the order as long as all the objects in the criteria array are moved to the top.

Any help would be greatly appreciated!

Thanks

Answer 1

Filter and concat

Since you don't care about the order other than these two groups and you know the larger array has all the elements from the smaller, rather than sorting, you could just filter all critarray items out of array than concatenate critarray and array :

 let array = [ {_id: "123", username: "username1",platform: "xbox"}, {_id: "124", username: "username2",platform: "xbox"}, {_id: "125", username: "username3",platform: "ps4"}, {_id: "126", username: "username4",platform: "pc"}, {_id: "127", username: "username5",platform: "ps4"}, {_id: "128", username: "username6",platform: "pc"} ]; let critarray = [ {_id: "124", username: "username2",platform: "xbox"}, {_id: "127", username: "username5",platform: "ps4"}, {_id: "128", username: "username6",platform: "pc"}, ]; // all items not in crit array let arrayFiltered = array.filter(item => !critarray.find(i => i._id === item._id) ) // concat critarray first, then rest let newArr = critarray.concat(arrayFiltered) console.log(newArr) 

This assumes _id is a unique identifier.

or Sort

Alternatively, you could also make a Set of ids from citarray and use inclusion in that set as the basis for sorting if you want to sort the array in place:

 let array = [ {_id: "123", username: "username1",platform: "xbox"}, {_id: "124", username: "username2",platform: "xbox"}, {_id: "125", username: "username3",platform: "ps4"}, {_id: "126", username: "username4",platform: "pc"}, {_id: "127", username: "username5",platform: "ps4"}, {_id: "128", username: "username6",platform: "pc"}, ]; let critarray = [ {_id: "124", username: "username2",platform: "xbox"}, {_id: "127", username: "username5",platform: "ps4"}, {_id: "128", username: "username6",platform: "pc"}, ]; let critIds = new Set critarray.forEach(item => critIds.add(item._id)) array.sort((a, b) => critIds.has(b._id) - critIds.has(a._id)) console.log(array)