string.md

string

codePointAt - Returns the UTF-16 encoded code point value of a position in a string

import { codePointAt } from 'src/string';

const str = 'string';
const position = 2; // zero index based position

const result = codePointAt(str, position);

result === 114; // true

endsWith - Determines whether a string ends with the given substring

import { endsWith } from 'src/string';

const str = 'string';
const search = 'ing';
const endPosition = str.length; // the index the searching should stop before

const result = endsWith(str, search, endPosition);

result === true; // true

fromCodePoint - Creates a string using the specified sequence of code points

import { fromCodePoint } from 'src/string';

const result = fromCodePoint(97, 98, 99, 49, 50, 51);

result === 'abc123'; // true

includes - Determines whether a string includes the given substring

import { includes } from 'src/string';

const str = 'string';
const search = 'ring';
const position = 0; // index to begin searching at

const result = includes(str, search, position);

result === true; // true

repeat - Returns a string containing a string repeated a given number of times

import { repeat } from 'src/string';

const str = 'string';
const times = 3; // the number of times to repeat the string

const result = repeat(str, times);

result === 'stringstringstring'; // true

startsWith - Determines whether a string begins with the given substring

import { startsWith } from 'src/string';

const str = 'string';
const search = 'str';

const result = startsWith(str, search);

result === true; // true

Special thanks to Mathias Bynens for granting permission to adopt code from his codePointAt, fromCodePoint, and repeat polyfills.

The string module also contains the following utility functions:

escapeRegExp - Escapes a string to safely be included in regular expressions

import { escapeRegExp } from 'src/string';

const str = 'cat file.js | grep -c';

const result = escapeRegExp(str);

result === 'cat file\\.js \\| grep -c'; // true

escapeXml - Escapes XML (or HTML) content in a string

import { escapeXml } from 'src/string';

const badCode = "<script>alert('hi')</script>";

const sanitized = escapeXml(badCode);

sanitized === '&lt;script&gt;alert(&#39;hi&#39;)&lt;/script&gt;'; // true

padEnd - Adds padding to the end of a string to ensure it is a certain length

import { padEnd } from 'src/string';

const str = 'string';
const length = 10;
const char = '=';

const result = padEnd(str, length, char);

result === 'string===='; // true

padStart - Adds padding to the beginning of a string to ensure it is a certain length

import { padStart } from 'src/string';

const str = 'string';
const length = 10;
const char = '=';

const result = padStart(str, length, char);

result === '====string'; // true