JavaScript String substr()

Extract a substring from text:

let text = "Hello world!";
let result = text.substr(1, 4);

Start at position 2:

let result = text.substr(2);

More examples below.

Description

The substr() method extracts a part of a string.

The substr() method begins at a specified position, and returns a specified number of characters.

The substr() method does not change the original string.

To extract characters from the end of the string, use a negative start position.

string.substr(start, length)

Parameter	Description
start	Required. The start position. First character is at index 0. If start is greater than the length, substr() returns "". If start is negative, substr() counts from the end of the string.
length	Optional. The number of characters to extract. If omitted, it extracts the rest of the string