AngularJS或Javascript：仅使用索引对数组（ASC和DESC）进行排序

Question

Assume i have a javascript object, like so:

var arrObject = [
{id:'01', name:'John'},
{id:'02', name:'Joseph'},
{id:'03', name:'Tom'},
{id:'04', name:'Nick'}
];

I have to sort the object in DESC order by index only. To sort, should not use any key from the object. Result:

var arrObject = [
{id:'04', name:'Nick'},
{id:'03', name:'Tom'},
{id:'02', name:'Joseph'},// to be remove
{id:'01', name:'John'},
];

Suppose I have deleted third item ie id = '02', and added new item object. Now, Object looks:

var arrObject = [
{id:'05', name:'Harrison'}, //new added item
{id:'04', name:'Nick'},
{id:'03', name:'Tom'},
{id:'01', name:'John'}
];

So, whenever I perform Add/Delete operation on the object I have to sort the array in DESC order by index only. That way I can keep the new item on top always and so on.

Note : No need to put the additional key in the object for sort purpose, as items from the object can be removed or added.

I do not see any built-in method would work for this directly, if yes that would great. If not, how would you go about writing a method that does this? Any help would be appreciated !!

Solution preferred in AngularJS, but Javascript also welcomed.

Answer 1

First - arrObject is an array of objects - this allows an index in the first place.

This issue seems to be a js only issue - simply use unshift() to add new items to the start of the array

 var arrObject = [ {id:'05', name:'Harrison'}, {id:'04', name:'Nick'}, {id:'03', name:'Tom'}, {id:'01', name:'John'} ]; arrObject.unshift({id:'06', name:'Gavin'}); console.log(arrObject); // puts the newly added Gavin object ar ethe start of the array. 

but if you really want to push an item to the end of the array then - .reverse() would seem to be what you want - ie array.reverse() will present the array from the end to the start

 var arrObject = [ {id:'01', name:'John'}, {id:'03', name:'Tom'}, {id:'04', name:'Nick'}, {id:'05', name:'Harrison'}, ]; arrObject.push({id:'06', name:'Gavin'});// puts the Gavin object ar ethe end of the array. console.log(arrObject.reverse()); // renders the array in reverse orderwith the Gavin object shown first