Can t access object property even though it shows up in a console log

Question

Below  you can see the output from these two logs  The first clearly shows the full object with the property I m trying to access  but on the very next line of code  I can t access it with config col id 3  see the  undefined  in the screenshot    Can anyone explain this  I can get access to every other property except field id 4 as well   console log config   console log config col id 3     This is what these lines print in Console

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I struggled with this issue today  and thought I ll leave a reply with my solution   I was fetching a data object via ajax  something like this    constants     value1   x   value2   y    i18n    data1   x    data2   y     Let s say this object is in a variable called data  Whenever I referenced data i18n I got undefined    console log data  showed the object as expected console log Object keys data   said   constants   i18n   as expected Renaming i18n to inter didn t change anything I even tried to switch the data to make  i18n  the first object Moved code around to make absolutely sure the object was completely set and  there was no problem with the ajax promise    Nothing helped    Then on the server side I wrote the data to the php log  and it revealed this     constants     value1   x   value2   y     u045618n    data1   x    data2   y     The  i  in the index key was actually a u0456  cyrillic i   This was not visible in my php editor or the browser console log  Only the php log revealed this    That was a tricky one

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The property you re trying to access might not exist yet  Console log works because it executes after a small delay  but that isn t the case for the rest of your code  Try this   var a   config col id 3       undefined  setTimeout function         var a   config col id 3       voila      100

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I was not getting the MongoDB error message in the thrown error in my NodeJS API response  so I did the following    It was not working console log error message     prints the error let response   error     message property was not available in the response           quot status quot    quot error quot      quot error quot          quot driver quot   true       quot name quot    quot MongoError quot        quot index quot   0       quot code quot   11000       quot keyPattern quot            quot event name quot   1             quot keyValue quot            quot event name quot    quot followup quot                     so I did this let message   error message  let response   JSON parse JSON stringify error    response message   message     message property is now available in the response           quot status quot    quot error quot      quot error quot          quot driver quot   true       quot name quot    quot MongoError quot        quot index quot   0       quot code quot   11000       quot keyPattern quot            quot event name quot   1             quot keyValue quot            quot event name quot    quot followup quot              quot message quot    quot E11000 duplicate key error collection  mycollections notificationevents index  event name 1 dup key    event name    quot followup  quot    quot

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I also had this frustrating problem  I tried the setTimeout   and the JSON stringify and JSON parse solutions even if I knew it wouldn t work as I think they re mostly JSON or Promise related problems  sure enough it didn t work  In my case though  I didn t notice immediately that it was a silly mistake  I was actually accessing a property name with a different casing  It s something like this   x000D   x000D  const wrongPropName    SomeProperty      upper case  S  const correctPropName    someProperty      lower case  s  const object     someProperty   hello world       console log  Accessing  SomeProperty     object wrongPropName    console log  Accessing  someProperty     object correctPropName   x000D   x000D   x000D   It took me a while to notice as the property names in my case can have either all lower case or some having mixed case  It turned out that a function in my web application has something that makes a mess of my property names  it has a  toLowerCase   next to the generated key names    So  lesson learned  check property name casing more properly

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I had the same issue and no solution above worked for me and it sort of felt like guess work thereafter  However  wrapping my code which creates the object in a setTimeout function did the trick for me    setTimeout function        var myObj   xyz    some code for creation of complex object like above    console log myObj      this works    console log myObj propertyName      this works too

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If this is an issue occurring when working with Mongoose  the following may happen  console log object   returns everything  including the desired key  console log object key   returns undefined  If that is happening  it means that the key is missing from the Mongoose Schema  Adding it in will resolve the issue

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if you re using TYPESCRIPT and or ANGULAR  it could be this    then  res  any    gt  res json     setting the response type to any fixed this issue for me  I couldn t access properties on the response until i set res  any  see this question Property   39  body  39  does not exist on type   39 Response  39

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In My case  it just happens to be that even though i receive the data in the format of a model like  myMethod data MyModelClass   object till the received object was of type string  Which is y in console log data  i get the content  Solution is just to parse the JSON in my case    const model MyMOdelClass JSON parse data     Thought may be usefull

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I just encountered this issue with objects generated by csv-parser from a CSV file that was generated by MS Excel  I was able to access all properties except the first property - but it would show up ok if I wrote the whole object using console log   Turned out that the UTF-8 CSV format inserts 3 bytes  ef bb bf  at the start corresponding to an invisible character - which were being included as part of the first property header by csv-parser  Solution was to re-generate the CSV using the non-UTF option and this eliminated the invisible character

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Just in case this is helpful for someone  I had a similar problem  and it s because someone created an override for  toJSON in the object I was working with   So the object was something like       foo             bar   Hello           baz   World               But  toJSON   was   toJSON       return this foo     So when I called JSON stringify myObject  it returned    bar    Hello    baz    World      However  Object keys myObject  revealed the  foo

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Check if inside the object there s an array of objects  I had a similar issue with a JSON        terms              category                                    ID   4                   name    Cirugia                    slug    cirugia                    description                        taxonomy    category                    parent   null                   count   68                   link    http   distritocuatro mx enarm category cirugia                                   I tried to access the  name  key from  category  and I got the undefined error  because I was using   var name   obj array terms category name   Then I realised it has got square brackets  that means that it has an array of objects inside the category key  because it can have more than one category object  So  in order to get the  name  key I used this   var name   obj array terms category 0  name   And That does the trick   Maybe it s too late for this answer  but I hope someone with the same problem will find this as I did before finding the Solution

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In 2018 Mozilla warns us in the Mozilla Docs here    I quote  Logging Objects       Don t use console log obj      use console log JSON parse JSON stringify obj           This way you are sure you are seeing the value of obj at the moment   you log it

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In my case I was passing an object to a promise  within the promise I was adding more key values to the object and when it was done the promise returned the object   However  a slight over look on my part  the promise was returning the object before it was fully finished   thus the rest of my code was trying to process the updated object and the data wasn t yet there   But like above  in the console  I saw the object fully updated but wasn t able to access the keys - they were coming back undefined   Until I saw this   console log obj    console log obj newKey1        returned in console  gt  Object   origKey1   blah   origKey2   blah blah    i      origKey1   blah      origKey2   blah blah      newKey1   this info      newKey2   that info      newKey3    more info   gt   undefined    The  i  is a little icon  when I hovered over it it said Object value at left was snapshotted when logged  value below was evaluated just now   Thats when it occurred to me that my object was being evaluated before the promise had fully updated it

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I had a similar issue today in React  Eventually realised that the problem was being caused by the state not being set yet  I was calling user user name and although it was showing up in the console  I couldn t seem to access it in my component till I included a check to check if user user was set and then calling user user name

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Check whether you had applied any filters in the console  It happens to me in chrome console

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I ve just had this issue with a document loaded from MongoDB using Mongoose   When running console log   on the whole object  all the document fields  as stored in the db  would show up  However some individual property accessors would return undefined  when others  including  id  worked fine   Turned out that property accessors only works for those fields specified in my mongoose Schema      definition  whereas console log   and JSON stringify   returns all fields stored in the db   Solution  if you re using Mongoose   make sure all your db fields are defined in mongoose Schema

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I had the same issue today  Problem was caused by uglify-js  After I executed same non-uglified code problem was solved  Removing of   --mangle-props   from uglify-js was enough to have working uglified code    Perhaps  the best practice is to use some prefix for properties that has to be mangled with regex rule for uglify-js   Here is the source   var data   JSON parse  content       this pageIndex   parseInt data index   this pageTotal   parseInt data total   this pageLimit   parseInt data limit      and here is how it was uglified   var n   JSON parse  t       this     parseInt n index   this g   parseInt n total   this D   parseInt n C

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I had a similar issue or maybe just related   For my case I was accessing properties of an object but one was undefined  I found the problem was a white-space in the server side code while creating the key val of the object   My approach was as follows             After removing the white-space from the server-side code creating the object  I could now access the property as below       This might not be the issue with the case of the subject question but was for my case and may be so for some one else  Hope it helps

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I had an issue like this  and found the solution was to do with Underscore js  My initial logging made no sense   console log JSON stringify obj  null  2      gt     gt     code    foo   gt     console log obj code     gt  undefined   I found the solution by also looking at the keys of the object   console log JSON stringify Object keys obj       gt     wrapped    chain     This lead me to realise that obj was actually an Underscore js wrapper around an object  and the initial debugging was lying to me

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My data was just json data string    This variable was stored as json string in the session     console log json string object    -  returns just the representation of this string and there is no way to make difference whether is string or object   So to make it work I just needed to convert it back to real object   object   JSON parse json string object

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I had similar problem  when developing for SugarCRM   where I start with   var leadBean   app data createBean  Leads    id  this model attributes parent id        This should load object with attributes  leadBean fetch        Here were my attributes filled in with proper values including name console log leadBean       Printed  undefined  console log leadBean attributes name     Problem was in fetch    its async call so I had to rewrite my code into   var leadBean   app data createBean  Leads    id  this model attributes parent id        This should load object with attributes  leadBean fetch       success  function  lead               Printed my value correctly         console log lead attributes name

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First thing check the type like below  console log typeof config    If the command above prints object then it is very easy you just use the bracket notation  Bracket notation can be quite useful if you want to search for a property   s values dynamically  Execute the command below  console log config col id 3     If it a string you need to parse in object first  To do that you need to execute the command below  var object   JSON parse config    And after that use bracket notation to access the property like below  console log object col id 3

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I ve just had the same issue with a document loaded from MongoDB using Mongoose   Turned out that i m using the property find   to return just one object  so i changed  find   to findOne   and everything worked for me   Solution  if you re using Mongoose   Make sure to return one object only  so you can parse its object id or it will be treated as an array so you need to acces it like that object 0  id

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I faced the same problem today  In my case the keys were nested  i e key1 key2  I split the keys using split   and then used the square bracket notation  which did work for me   var data         key1              key2   some value               I split the keys and used it like this  data key1  key2  which did the job for me

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I had the same issue  Solution for me was using the stringified output as input to parsing the JSON  this worked for me  hope its useful to you  var x  JSON parse JSON stringify obj    console log x property actually now defined

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I just encountered this issue as well  and long story short my API was returning a string type and not JSON    So it looked exactly the same when you printed it to the log however whenever I tried to access the properties it gave me an undefined error   API Code        var response   JsonConvert DeserializeObject lt StatusResult gt  string Of object        return Json response     previously I was just returning   return Json string Of object

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This might help somebody as I had a similar issue in which the JSON parse   was returning an object that I could print on the console log   but I couldn t acccess the specific fields and none of the above solution worked for me  Like using the combination of JSON parse   with JSON stringify     var jsonObj   JSON parse JSON stringify responseText       where responseText is a JSON String returned by the server   console log jsonObj     Was printing the object correctly console log jsonObj Body      Was printing Undefined     I ended up solving the problem by using a different parser provided by ExtJs Ext decode     var jsonObj   Ext decode responseText  console log jsonObj Body    Worked

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For me it turned out to be a Mongoose-related problem   I was looping over objects that I got from a Mongo query  I just had to remove   items   await Model find     And replace it by   items   await Model find   lean

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None of the JSON stringify parse worked for me    formValues myKey                undefined formValues myKey with timeout   content   I wanted the value of formValues myKey and what did the trick was a setTimeout 0 like in the example below  Hope it helps   console log  formValues myKey    formValues myKey   setTimeout       gt       console log  formValues myKey with timeout     formValues myKey      0

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The output of console log anObject  is misleading  the state of the object displayed is only resolved when you expand the Object tree displayed in the console  by clicking on  gt   It is not the state of the object when you console log d the object  Instead  try console log Object keys config    or even console log JSON stringify config   and you will see the keys  or the state of the object at the time you called console log  You will  usually  find the keys are being added after your console log call

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I ve had similar issue  hope the following solution helps someone  You can use setTimeout function as some guys here suggesting  but you never know how exactly long does your browser need to get your object defined   Out of that I d suggest using setInterval function instead  It will wait until your object config col id 3 gets defined and then fire your next code part that requires your specific object properties   window addEventListener  load   function         var fileInterval   setInterval function             if  typeof config col id 3      undefined                     do your stuff here              clearInterval fileInterval      clear interval                  100      check every 100ms

[javascript] Can't access object property, even though it shows up in a console log

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