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Created April 6, 2012 17:40
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Get a nested object property by passing a dot notation string as the property name
* A function to take a string written in dot notation style, and use it to
* find a nested object property inside of an object.
* Useful in a plugin or module that accepts a JSON array of objects, but
* you want to let the user specify where to find various bits of data
* inside of each custom object instead of forcing a standardized
* property list.
* @param String nested A dot notation style parameter reference (ie "urls.small")
* @param Object object (optional) The object to search
* @return the value of the property in question
function getProperty( propertyName, object ) {
var parts = propertyName.split( "." ),
length = parts.length,
property = object || this;
for ( i = 0; i < length; i++ ) {
property = property[parts[i]];
return property;
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Masterful function. Just what I needed :) 🥇

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dolapci commented May 17, 2018

This is what i needed :) thank you

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laxa88 commented May 18, 2018

@jasonrhodes Awesome little gem here, thank you!

Just wanted to point out that this snippet fails if the property doesn't exist, e.g.:

getProperty('a.b.c', {a:{b:{}}});

Would there be any complications if I do a try ... catch in the loop and return undefined if it throws?

EDIT: just noticed the post by @doublejosh , seems like there's a simpler solution without involving try/catch. cheers!

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hi dudes

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is there anybody help me about angular 6?

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@laxa88 Hi

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my3sons commented Sep 10, 2018

I tried 10 other examples before this that all failed miserably, yours worked like a charm, thanks!

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How can I get this working for something like obj->geometry[6]->obs[3]->latitude ?

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mp2468 commented Dec 27, 2019

Would anyone know how to do this to handle array as well? like being able to do
myVal = getDescendantProp(myData, 'someProperty.deeperProperty[0].evendeeperproperty');

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DavChi commented Apr 21, 2020

@mp2468 Based on this, we could use regex to handle both dot notation and bracket notation path.

const getDescendantProp = (obj, path) => {
  const arr = path.split(/[.[]['"]?/);
  let o = obj;
  while (arr.length && o) {
    o = o[arr.shift().replace(/['"]?]$/, '')];
  return o;

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kissu commented Jan 7, 2021

A functional answer might be (es2015 just because):

const getDescendantProp = (obj, path) => (
    path.split('.').reduce((acc, part) => acc && acc[part], obj)

Damn man, it doesn't even error if the path is not valid (no optional chaining needed), L33T. Thanks ! ❤️

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