Each for object

Question

I have object in JavaScript   var object   someobject   Object   aaa true  bbb true  ccc true     How can I use each for this    object each function index  value           console log value        Not working

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x000D   x000D  var object      a   1   b   2   x000D    each object  function key  value   x000D    console log key          object key    x000D      x000D   lt script src  https   ajax googleapis com ajax libs jquery 2 0 0 jquery min js  gt  lt  script gt  x000D   x000D   x000D      output a  1 b  2

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A javascript Object does not have a standard  each function  jQuery provides a function  See http   api jquery com jQuery each  The below should work    each object  function index  value        console log value          Another option would be to use vanilla Javascript using the Object keys   and the Array  map   functions like this  Object keys object  map function objectKey  index        var value   object objectKey       console log value         See https   developer mozilla org nl docs Web JavaScript Reference Global Objects Object keys and https   developer mozilla org en-US docs Web JavaScript Reference Global Objects Array map  These are usually better than using a vanilla Javascript for-loop  unless you really understand the implications of using a normal for-loop and see use for it s specific characteristics like looping over the property chain    But usually  a for-loop doesn t work better than jQuery or Object keys   map    I ll go into two potential issues with using a plain for-loop below     Right  so also pointed out in other answers  a plain Javascript alternative would be  for var index in object         var attr   object index        There are two potential issues with this   1   You want to check whether the attribute that you are finding is from the object itself and not from up the prototype chain  This can be checked with the hasOwnProperty function like so  for var index in object        if  object hasOwnProperty index            var attr   object index            See https   developer mozilla org en-US docs Web JavaScript Reference Global Objects Object hasOwnProperty for more information    The jQuery each and Object keys functions take care of this automatically   2   Another potential issue with a plain for-loop is that of scope and non-closures  This is a bit complicated  but take for example the following code  We have a bunch of buttons with ids button0  button1  button2 etc  and we want to set an onclick on them and do a console log like this    lt button id  button0  gt click lt  button gt   lt button id  button1  gt click lt  button gt   lt button id  button2  gt click lt  button gt   var messagesByButtonId     button0     clicked first     button1     clicked middle     button2     clicked last     for var buttonId in messagesByButtonId         if  messagesByButtonId hasOwnProperty buttonId                  buttonId  click function                var message   messagesByButtonId buttonId              console log message                       If  after some time  we click any of the buttons we will always get  clicked last   in the console  and never  clicked first   or  clicked middle    Why  Because at the time that the onclick function is executed  it will display messagesByButtonId buttonId  using the buttonId variable at that moment  And since the loop has finished at that moment  the buttonId variable will still be  button2   the value it had during the last loop iteration   and so messagesByButtonId buttonId  will be messagesByButtonId  button2    i e   clicked last     See https   developer mozilla org en-US docs Web JavaScript Closures for more information on closures  Especially the last part of that page that covers our example   Again  jQuery each and Object keys   map   solve this problem automatically for us  because it provides us with a function index  value   that has closure  so we are safe to use both index and value and rest assured that they have the value that we expect

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for var key in object       console log object key

[javascript] Each for object?

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