Data types in TypeScript
When you create a variable, you’re planning to give it a value. But what kind of value it can hold depends on the variable’s data type. In TypeScript, the type system defines the various data types supported by the language. The data type classification is as given below:
Built-in Datatypes:
TypeScript has some pre-defined data-types-
| Built-in Data Type | keyword | Description |
|---|---|---|
| Number | number | It is used to represent both Integer as well as Floating-Point numbers |
| Boolean | boolean | Represents true and false |
| String | string | It is used to represent a sequence of characters |
| Void | void | Generally used on function return-types |
| Null | null | It is used when an object does not have any value |
| Undefined | undefined | Denotes value given to uninitialized variable |
| Any | any | If variable is declared with any data-type then any type of value can be assigned to that variable |
Examples:
let a: null = null; let b: number = 123; let c: number = 123.456; let d: string = ‘Beginner’; let e: undefined = undefined; let f: boolean = true; let g: number = 0b111001; // Binary let h: number = 0o436; // Octal let i: number = 0xadf0d; // Hexa-Decimal
User-defined Data Types:
Apart from built-in data types, user can also define its own data type. User-defined types include Enumerations (enums), classes, interfaces, arrays, and tuple.
NOTE:
In built-in data types,
any:
is a special data-type, also the super data-type of all data types. If a variable is declared with any data type then we can assign any type value to that variable.
Examples:
let a: any = null; let b: any =123; let c: any = 123.456; let d: any = ‘Beginner’; let e: any = undefined; let f: any = true;