Deep Get

Get a nested property value.

Usage

var deepGet = require( '@stdlib/utils/deep-get' );

deepGet( obj, path[, options] )

Returns a nested property value.

var obj = { 'a': { 'b': { 'c': 'd' } } };

var val = deepGet( obj, 'a.b.c' );
// returns 'd'

For paths including arrays, specify the numeric index.

var arr = [
    { 'a': [ {'x': 5} ] },
    { 'a': [ {'x': 10} ] }
];

var val = deepGet( arr, '1.a.0.x' );
// returns 10

The key path may be specified as either a delimited string or a key array.

var obj = { 'a': { 'b': { 'c': 'd' } } };

var val = deepGet( obj, [ 'a', 'b', 'c' ] );
// returns 'd'

The function accepts the following options:

  • sep: key path separator. Default: '.'.

By default, the function assumes dot separated key values. To specify an alternative separator, set the sep option.

var obj = { 'a': { 'b': { 'c': 'd' } } };

var val = deepGet( obj, 'a/b/c', {
    'sep': '/'
});
// returns 'd'

deepGet.factory( path[, options] )

Creates a reusable deep get function. The factory method ensures a deepGet function is configured identically by using the same set of provided options.

var dget = deepGet.factory( 'a/b/c', {
    'sep': '/'
});

dget( obj )

Returns a nested property value.

var dget = deepGet.factory( 'a.b.c' );

var obj = { 'a': { 'b': { 'c': 'd' } } };

var val = dget( obj );
// returns 'd'

Examples

var randu = require( '@stdlib/random/base/randu' );
var deepGet = require( '@stdlib/utils/deep-get' );

var data;
var keys;
var val;
var i;

data = new Array( 100 );
for ( i = 0; i < data.length; i++ ) {
    data[ i ] = {
        'x': Date.now(),
        'y': [ randu(), randu(), i ]
    };
}

keys = [ 0, 'y', 2 ];
for ( i = 0; i < data.length; i++ ) {
    keys[ 0 ] = i;
    val = deepGet( data, keys );
    console.log( val );
}