Return the part of a string after a specified substring.
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> Return the part of a string after a specified substring.
``bash`
npm install @stdlib/string-substring-after
`javascript`
var substringAfter = require( '@stdlib/string-substring-after' );
#### substringAfter( str, search\[, fromIndex] )
Returns the part of a string after a specified substring.
`javascript
var str = 'beep boop';
var out = substringAfter( str, 'o' );
// returns 'op'
out = substringAfter( str, ' ' );
// returns 'boop'
`
By default, the search starts at the beginning of the string. To start searching from a different index, provide a fromIndex argument:
`javascript`
var str = 'boop baz boop';
var out = substringAfter( str, 'o', 3 );
// returns 'op'
- If a substring is not present in a provided string, the function returns an empty string.
- If provided an empty substring, the function returns the input string.
- If fromIndex is less than 0 or greater than str.length, the search starts at index 0 and str.length, respectively.
`javascript
var substringAfter = require( '@stdlib/string-substring-after' );
var str = 'To be, or not to be, that is the question.';
var out = substringAfter( str, ', ' );
// returns 'or not to be, that is the question.'
out = substringAfter( str, 'to be' );
// returns ', that is the question.'
out = substringAfter( str, 'question.' );
// returns ''
out = substringAfter( str, 'xyz' );
// returns ''
out = substringAfter( str, '' );
// returns 'To be, or not to be, that is the question.'
`
- [@stdlib/string-substring-after-cli][@stdlib/string-substring-after-cli]: CLI package for use as a command-line utility.
- [@stdlib/string-substring-before][@stdlib/string/substring-before]: return the part of a string before a specified substring.
- [@stdlib/string-substring-before-last][@stdlib/string/substring-before-last]: return the part of a string before the last occurrence of a specified substring.
- [@stdlib/string-substring-after-last][@stdlib/string/substring-after-last]: return the part of a string after the last occurrence of a specified substring.
*
This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.
For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].
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---
See [LICENSE][stdlib-license].
Copyright © 2016-2026. The Stdlib [Authors][stdlib-authors].
[@stdlib/string-substring-after-cli]: https://www.npmjs.com/package/@stdlib/string-substring-after-cli
[npm-image]: http://img.shields.io/npm/v/@stdlib/string-substring-after.svg
[npm-url]: https://npmjs.org/package/@stdlib/string-substring-after
[test-image]: https://github.com/stdlib-js/string-substring-after/actions/workflows/test.yml/badge.svg?branch=v0.2.3
[test-url]: https://github.com/stdlib-js/string-substring-after/actions/workflows/test.yml?query=branch:v0.2.3
[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/string-substring-after/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/string-substring-after?branch=main
[chat-image]: https://img.shields.io/badge/zulip-join_chat-brightgreen.svg
[chat-url]: https://stdlib.zulipchat.com
[stdlib]: https://github.com/stdlib-js/stdlib
[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors
[cli-section]: https://github.com/stdlib-js/string-substring-after#cli
[cli-url]: https://github.com/stdlib-js/string-substring-after/tree/cli
[@stdlib/string-substring-after]: https://github.com/stdlib-js/string-substring-after/tree/main
[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules
[deno-url]: https://github.com/stdlib-js/string-substring-after/tree/deno
[deno-readme]: https://github.com/stdlib-js/string-substring-after/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/string-substring-after/tree/umd
[umd-readme]: https://github.com/stdlib-js/string-substring-after/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/string-substring-after/tree/esm
[esm-readme]: https://github.com/stdlib-js/string-substring-after/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/string-substring-after/blob/main/branches.md
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/string-substring-after/main/LICENSE
[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams
[mdn-regexp]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions
[@stdlib/string/substring-before]: https://www.npmjs.com/package/@stdlib/string-substring-before
[@stdlib/string/substring-before-last]: https://www.npmjs.com/package/@stdlib/string-substring-before-last
[@stdlib/string/substring-after-last]: https://www.npmjs.com/package/@stdlib/string-substring-after-last