TypeScript Array concat() Method (original) (raw)

Last Updated : 19 Jul, 2024

The **TypeScript Array.concat() method merges two or more arrays into a new array. It takes multiple arrays and/or values as parameters and returns a single array containing all the elements. This method helps efficiently combine data from various sources into one array.

**Syntax

array.concat(value1, value2, ..., valueN)

**Parameter: This method accepts a single parameter multiple times as mentioned above and described below:

• **valueN: These parameters are arrays and/or values to concatenate.

**Return Value: The method returns a new array containing all elements of the original array followed by the elements of the concatenated arrays and/or values.

The below examples illustrate the **Array concat() method in TypeScript.

**Example 1: Concatenating Three Arrays of Numbers

The TypeScript code defines three arrays, then concatenates them using the concat() method and logs the result to the console.

JavaScript `

const array1: number[] = [11, 12, 13]; const array2: number[] = [14, 15, 16]; const array3: number[] = [17, 18, 19];

const newArray: number[] = array1.concat(array2, array3); console.log(newArray);

`

**Output:

[ 11, 12, 13, 14, 15, 16, 17, 18, 19 ]

**Example 2: Merging Two Arrays of Strings

In TypeScript, define two arrays of strings, then merge them using the concat() method.

JavaScript `

const arrayA: string[] = ['a', 'b', 'c']; const arrayB: string[] = ['d', 'e', 'f'];

const mergedArray: string[] = arrayA.concat(arrayB); console.log(mergedArray);

`

**Output:

[ 'a', 'b', 'c', 'd', 'e', 'f' ]