What are the several types of data types in js?
JavaScript data types are divided into the following categories: Basic types: Number, String, Boolean, Null, Undefined Object types: Object, Array, Function, Date, RegExp Special types: Symbol, BigInt You can use the typeof operator Determine the data type.
Data types in JS
The data types in JavaScript are mainly divided into the following categories:
1. Basic types
- #Number: Numerical type, including integers and floating point numbers.
- String: String type, consisting of a series of characters.
-
Boolean: Boolean type, can only be
true
orfalse
. - Null: Null value type, representing an unknown or non-existent value.
- Undefined: Undefined type, indicating that a variable has not yet been assigned a value.
2. Object type
- Object: Object type, which can store key-value pairs.
- Array: Array type, which can store a set of sequential data.
- Function: Function type is a set of reusable code blocks.
- Date: Date type, representing time and date information.
- RegExp: Regular expression type, used for matching and processing strings.
3. Special types
- Symbol: Symbol type is a unique identifier.
- BigInt: The BigInt type is used to store integers larger than the Number type.
How to determine the data type
You can use the typeof
operator to determine the data type of a variable. For example:
typeof 42; // "number" typeof "Hello"; // "string" typeof true; // "boolean" typeof null; // "object" typeof undefined; // "undefined"
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