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pick()

pick<T, K>(object, keys): Pick<T, K>

Creates a new object with only the specified keys.

note

Non-existent keys are ignored.

Type Parameters​

T: T extends Record<PropertyKey, any>​

The type of the input object.

K: K extends string | number | symbol​

The type of the keys to pick.

Parameters​

object: T​

The object to pick keys from.

keys: readonly K[]​

Array of keys to pick.

Returns: Pick<T, K>​

A new object with only the specified keys.

See Also​

Since​

2.0.0

Performance​

O(k) time & space where k is number of keys to pick. Uses for-of loop and hasOwnProperty check.

Also known as​

objectPick (Antfu) · pick (Lodash, es-toolkit, Remeda, Radashi, Ramda, Effect, Modern Dash)

Example​

const obj = { a: 1, b: 2, c: 3 };

pick(obj, ['a', 'c']); // => { a: 1, c: 3 }
pick(obj, ['b']);      // => { b: 2 }

const user = { id: 1, name: 'John', password: 'secret' };
pick(user, ['id', 'name']); // => { id: 1, name: 'John' }

How it works?​

Creates a new object with only the specified keys.

Selection Process​

pick vs omit​

pickomit
Keepsspecified keysall except specified
Use casewhitelistblacklist

Use Cases​

Select specific subsets 📌​

Create a shallow copy containing only the specified keys. Critical for creating strict DTOs or filtering API payloads.

const payload = pick(formData, ['username', 'email']);

Extract form subset for validation​

Select only the fields relevant to a specific validation step. Useful for multi-step forms or partial schema validation.

const step1Data = pick(formData, ['firstName', 'lastName', 'email']);
const isValid = validateStep1Schema(step1Data);

Whitelist allowed parameters​

Ensure that only permitted keys are passed to a function or API. Security critical for preventing mass assignment vulnerabilities.

const safeInput = pick(req.body, ['title', 'content', 'authorId']);
db.create(safeInput);

Extract safe fields for logging​

Pick only non-sensitive fields before writing to logs. Critical for compliance (GDPR, HIPAA) and preventing PII leaks in log systems.

const request = {
  userId: "u-123",
  endpoint: "/api/checkout",
  method: "POST",
  creditCard: "4111-1111-1111-1111",
  ip: "192.168.1.1",
  timestamp: 1703001200,
};

const safeLog = pick(request, ["userId", "endpoint", "method", "timestamp"]);
logger.info("API request", safeLog);
// Logs: { userId: "u-123", endpoint: "/api/checkout", method: "POST", timestamp: 1703001200 }
// Credit card and IP never reach the logs

Build chart dataset from raw records​

Extract only the fields needed for chart rendering from complex records. Essential for transforming API data into chart-compatible formats.

const salesRecords = [
  { id: 1, product: "Widget", revenue: 5000, cost: 2000, date: "2025-01", region: "EU" },
  { id: 2, product: "Gadget", revenue: 8000, cost: 3500, date: "2025-02", region: "US" },
];

const chartData = salesRecords.map((r) => pick(r, ["date", "revenue", "cost"]));
// => [{ date: "2025-01", revenue: 5000, cost: 2000 }, ...]
renderBarChart(chartData);

Extract preset fields for saving user preferences​

Pick only the saveable fields from a large settings object. Perfect for saving user presets without storing transient UI state.

const fullSettings = {
  theme: "dark",
  fontSize: 16,
  language: "fr",
  sidebarOpen: true,
  lastVisitedPage: "/dashboard",
  unsavedChanges: true,
};

const presetData = pick(fullSettings, ["theme", "fontSize", "language"]);
// => { theme: "dark", fontSize: 16, language: "fr" }
localStorage.setItem("user-preset", JSON.stringify(presetData));