Jun 5, 2024 · In JavaScript, `null` indicates the deliberate absence of any object value. It’s a primitive value that denotes the absence of a value or serves as a placeholder for an object that isn’t present. `null` differs from `undefined`, which signifies a variable that has been declared but hasn’t been assigned a value.

Jan 4, 2024 · To check for null SPECIFICALLY you would use this: if (variable === null) This test will ONLY pass for null and will not pass for "", undefined, false, 0, or NaN. Additionally, I've provided absolute checks for each "false-like" value (one that would return true for !variable).

Sep 17, 2024 · undefined indicates a variable hasn’t been initialized, while null is intentionally assigned to indicate no value. Understanding the distinction helps write cleaner, more predictable code in JavaScript, especially when handling default values or checking for missing data.

Nowadays most browsers support the Nullish coalescing operator (??) and the Logical nullish assignment (??=), which allows a more concise way to assign a default value if a variable is null or undefined, for example:

JavaScript uses the null value to represent the intentional absence of any object value. If you find a variable or a function that returns null, it means that the expected object couldn’t be created. …

Mar 13, 2025 · The null value represents the intentional absence of any object value. It is one of JavaScript's primitive values and is treated as falsy for boolean operations.

Using the == operator, you can reliably use null and undefined interchangeably as far as I can tell. However, because of the advantage that null cannot be redefined, I might would use it when using ==.

In this tutorial, you will learn about null and undefined data types available in JavaScript with the help of examples.

Sep 21, 2020 · In this post, you'll learn everything about null in JavaScript: its meaning, how to detect it, the difference between null and undefined, and why using null extensively creates code maintenance difficulties.

Jun 2, 2023 · In JavaScript, the null keyword is a primitive value that represents the intentional absence of any object value. It is often used to indicate that a variable does not currently have a value or does not refer to any object. Here’s how the null keyword works in JavaScript: