Dynamic Array Keys

Dynamic array keys

This is kind of non-trivial because you want to nest, but it should go something like:

function insert_using_keys($arr, $keys, $value){
    // we're modifying a copy of $arr, but here
    // we obtain a reference to it. we move the
    // reference in order to set the values.
    $a = &$arr;

    while( count($keys) > 0 ){
        // get next first key
        $k = array_shift($keys);

        // if $a isn't an array already, make it one
        if(!is_array($a)){
            $a = array();
        }

        // move the reference deeper
        $a = &$a[$k];
    }
    $a = $value;

    // return a copy of $arr with the value set
    return $arr;
}

Dynamically creating keys in a JavaScript associative array

Use the first example. If the key doesn't exist it will be added.

var a = new Array();
a['name'] = 'oscar';
alert(a['name']);

Will pop up a message box containing 'oscar'.

Try:

var text = 'name = oscar'
var dict = new Array()
var keyValuePair = text.replace(/ /g,'').split('=');
dict[ keyValuePair[0] ] = keyValuePair[1];
alert( dict[keyValuePair[0]] );

Sum array of objects with dynamic keys - Javascript

Here's my solution. Map through the array and flatten the properties values, then reduce them.

const arr = [
  { 'Atencion Personalizada': 2, 'Caja': 3 },
  { 'Atencion Personalizada': 1 },
  { 'Tarifa Social': 3 }
]

console.log(arr.flatMap(e => Object.values(e)).reduce((a, b) => a + b));

Create Array by Dynamic Keys and Values

let name = 'Vishesh';
let name2 = 'Vishesh2';
let cars = [{carName: "Mercedes"},{carName: "Volvo"},{carName:"BMW"}];
let array = []

array.push({[name]:cars})
array.push({[name2]:cars})
console.log(array);

loop through a dynamic key of an object in a array

Just use the Bracket notation:

additionalFields.map((opts) => {
  if(fields[opts].length > 0){ //this one doesn't work...
    //do something
  }
}

Example:

const person = {
  firstname: 'John',
  lastname: 'Doe'
}

const key = "firstname"
console.log(person[key]) // John

Dynamic keys in Javascript associative array declaration one-liner

It is now possible to use dynamic keys in the declaration of a javascript object, in any browser/platform that supports ES6 literal shorthands:

key = "dynamic";    
arr2 = {
    [key]: "foo",  // "dynamic": "foo"
    "bar": "baz"
};

Reduce Array of Objects with Dynamic Keys

Get the key/value pairs and update the sum.

var data = [{ A: 4, B: 2 }, { A: 2, B: 1 }, { A: 3, B: 1 }, { A: 2, B: 1, C: 1 }],    result = data.reduce((r, o) => (Object.entries(o).forEach(([k, v]) => r[k] = (r[k] || 0) + v), r), {});
console.log(result);

TypeScript array.map() with dynamic keys

You can probably do this by creating a new object in the map and returning it?

Something like

const fooArrayWithLimitedKeys = fooArray.map(item => arrayOfKeys.reduce(
  (accumulator, key) => {
    accumulator[key] = item[key]
    return accumulator
  }, {})
)

it can also be written without reduce like follows:

const fooArrayWithLimitedKeys = fooArray.map(item => {
  const returnValue = {}
  arrayOfKeys.forEach(key => {
    returnValue[key] = item[key]
  })
  return returnValue;
})

KQL - Convert Dynamic Array of Key Value to Key Value dictionary

you can use a combination of mv-apply and make_bag():

print d = dynamic([
  {"key": "value"},
  {"ProjectId": "1234"},
  {"ProjectName": "Albatros"},
  {"User": "Bond"}
])
| mv-apply d on (
    summarize result = make_bag(d)
)

for (var i = 0; i <= trackobj.trackees.length; i++) {
    for(var key in trackobj.trackees[i]) {
        console.log(key);
    }
}