Removing object properties with Lodash

Question

I have to remove unwanted object properties that do not match my model  How can I achieve it with Lodash  My model is  var model        fname  null     lname  null    My controller output before sending to the server will be  var credentials         fname   quot xyz quot       lname   quot abc quot       age  23    If I use    extend model  credentials   I am getting the age property too  I am aware I can use delete credentials age  but what if I have more than 10 unwanted objects  Can I achieve it with Lodash

User · Answer

You can easily do this using   pick   x000D   x000D  var model       fname  null    lname  null     var credentials       fname   abc     lname   xyz     age  2     var result     pick credentials    keys model      console log  result     result   x000D   lt script src  https   cdn jsdelivr net lodash 4 16 4 lodash min js  gt  lt  script gt  x000D   x000D   x000D   But you can simply use pure JavaScript  specially if you use ECMAScript  6   like this   x000D   x000D  const model       fname  null    lname  null     const credentials       fname   abc     lname   xyz     age  2     const newModel        Object keys model  forEach key   gt  newModel key    credentials key     console log  newModel     newModel   x000D   x000D   x000D

User · Answer

To select  or remove  object properties that satisfy a given condition deeply  you can use something like this   function pickByDeep object  condition  arraysToo false      return   transform object   acc  val  key    gt        if    isPlainObject val     arraysToo  amp  amp    isArray val           acc key    pickByDeep val  condition  arraysToo         else if  condition val  key  object           acc key    val                  https   codepen io aercolino pen MWgjyjm

User · Answer

You can approach it from either an  quot allow list quot  or a  quot block list quot  way     Block list    Remove the values you don t want var result     omit credentials    age         Allow list    Only allow certain values var result     pick credentials    fname    lname      If it s reusable business logic  you can partial it out as well     Partial out a  quot block list quot  version var clean     partial   omit       age         and later var result   clean credentials    Note that Lodash 5 will drop support for omit A similar approach can be achieved without Lodash  const transform    obj  predicate    gt      return Object keys obj  reduce  memo  key    gt        if predicate obj key   key           memo key    obj key            return memo             const omit    obj  items    gt  transform obj   value  key    gt   items includes key    const pick    obj  items    gt  transform obj   value  key    gt  items includes key       Partials    Lazy clean const cleanL    obj    gt  omit obj    age        Guarded clean const cleanG    obj    gt  pick obj    fname    lname          quot App quot  const credentials         fname  quot xyz quot       lname  quot abc quot       age 23    const omitted   omit credentials    age    const picked   pick credentials    age    const cleanedL   cleanL credentials  const cleanedG   cleanG credentials

User · Answer

Lodash unset is suitable for removing a few unwanted keys   x000D   x000D  const myObj         keyOne   hello       keyTwo   world     unset myObj   keyTwo     console log myObj       myObj     keyOne   hello    x000D   x000D   x000D

User · Answer

You can use   omit   for emitting the key from a JSON array if you have fewer objects    forEach data   d    gt          omit d    keyToEmit1    keyToEmit2         If you have more objects  you can use the reverse of it which is   pick      forEach data   d    gt          pick d    keyToPick1    keyToPick2

User · Answer

This is my solution to deep remove empty properties with Lodash  const compactDeep   obj   gt        const emptyFields            function calculateEmpty prefix  source              each source   val  key    gt               if    isObject val   amp  amp     isEmpty val                     calculateEmpty    prefix   key     val                 else if      isBoolean val   amp  amp     isNumber val   amp  amp   val        isObject val   amp  amp    isEmpty val                      emptyFields push    prefix   key                                          calculateEmpty     obj        return   omit obj  emptyFields

User · Answer

Here I have used omit   for the respective  key  which you want to remove    by using the Lodash library  var credentials              fname   quot xyz quot           lname   quot abc quot           age  23     let result     map credentials  object   gt                           return   omit object    fname    lname                           console log  result   result

User · Answer

Get a list of properties from model using   keys    and use   pick   to extract the properties from credentials to a new object   x000D   x000D  var model        fname null     lname null     var credentials         fname  xyz       lname  abc       age 23     var result     pick credentials    keys model     console log result   x000D   lt script src  https   cdnjs cloudflare com ajax libs lodash js 4 16 4 lodash min js  gt  lt  script gt  x000D   x000D   x000D   If you don t want to use Lodash  you can use Object keys    and Array prototype reduce     x000D   x000D  var model        fname null     lname null     var credentials         fname  xyz       lname  abc       age 23     var result   Object keys model  reduce function obj  key      obj key    credentials key     return obj           console log result   x000D   x000D   x000D

[lodash] Removing object properties with Lodash

Examples related to lodash