getting the last item in a javascript object

Question

If I have an object like       a     apple    b     banana    c     carrot      If I don t know in advance that the list goes up to  c   other than looping through the object  is there a way to get the last item in the object  e g   carrot

User · Answer

As for the ordering of object properties in Javascript, I will just link to this answer:

Elements order in a "for (… in …)" loop

Specifically:

All modern implementations of ECMAScript iterate through object properties in the order in which they were defined

So every other answer here is correct, there is no official guaranteed order to object properties. However in practice there is (barring any bugs which naturally can screw up even set-in-stone officially specified behavior).

Furthermore, the de-facto enumeration order of object properties is likely to be codified in future EMCAScript specs.

Still, at this time I would not write code around this, mostly because there are no built-in tools to help deal with object property order. You could write your own, but in the end you'd always be looping over each property in an object to determine its position.

As such the answer to your question is No, there is no way besides looping through an object.

User · Answer

if you mean get the last key alphabetically  you can  garanteed     var obj      a     apple    b     banana    c     carrot     var keys   Object keys obj   keys sort    var lastkey   keys pop      c var lastvalue   obj lastkey      carrot

User · Answer

Map object in JavaScript   This is already about 3 years old now  This map data structure retains the order in which items are inserted  With this retrieving last item will actually result in latest item inserted in the Map

User · Answer

Use an array  not an object literal  if order matters    list     apple    banana    carrot      Or something like  dict       a      apple    awesome      b      best friend        Or even    dict     letter  a   list   apple    awesome     letter  b   list   best friend        The keys for dict are not guaranteed at all to be in order

User · Answer

Let obj be your object  Exec        gt    Object keys    pop      obj

User · Answer

JSArray      a     apple    b     banana    c     carrot       document write Object keys JSArray  Object keys JSArray  length-1      writes  c     document write JSArray Object keys JSArray  Object keys JSArray  length-1        writes  carrot

User · Answer

The other answers overcomplicate it for me   let animals       a   dog     b   cat     c   bird     let lastKey   Object keys animals  pop   let lastValue   animals Object keys animals  pop

User · Answer

last   Object keys obj  Object keys obj  length-1     where obj is your object

User · Answer

No  Order is not guaranteed in JSON and most other key-value data structures  so therefore the last item could sometimes be carrot and at other times be banana and so on  If you need to rely on ordering  your best bet is to go with arrays   The power of key-value data structures lies in accessing values by their keys  not in being able to get the nth item of the object

User · Answer

You can try this  This will store last item  Here need to convert obj into array  Then use array pop   function that will return last item from converted array    x000D   x000D  var obj      a     apple    b     banana    c     carrot     x000D  var last   Object keys obj  pop    x000D  console log last   x000D  console log obj last    x000D   x000D   x000D

User · Answer

Yes  there is a way using Object keys obj   It is explained in this page   var fruitObject      a     apple    b     banana    c     carrot     Object keys fruitObject      this returns all properties in an array   a    b    c     If you want to get the value of the last object  you could do this   fruitObject Object keys fruitObject  Object keys fruitObject  length - 1       carrot

User · Answer

var myObj    a  1  b  2  c  3   lastProperty  for  lastProperty in myObj   lastProperty     c     source http   javascriptweblog wordpress com

User · Answer

Solution using the destructuring assignment syntax of ES6    x000D   x000D  var temp      a     apple    b     banana    c     carrot     x000D  var    Object keys temp  pop     lastItem     temp  x000D  console info lastItem      carrot  x000D   x000D   x000D

User · Answer

You could also use the Object values   method   Object values fruitObject  Object values fruitObject  length - 1       carrot

[javascript] getting the last item in a javascript object

Examples related to javascript

Examples related to object