While we believe that this content benefits our community, we have not yet thoroughly reviewed it. If you have any suggestions for improvements, please let us know by clicking the “report an issue“ button at the bottom of the tutorial.
String.prototype.match() (aka: the match method on strings) can allow you to switch out strings or set conditions if a string or any data is matched. It then stores that data in a new array.
First the syntax and then the explanation:
let newArray = string.match(condition);
match() method will return an array with the items being matches from a provided
Remember, when all conditions are matched, those results will be stored in a new array.
Take the following example:
const intro = "Hello Alligators, Hello Devs, how are you?" const regex = /Hello/g; const greeting = intro.match(regex);
The above will give us an array like this:
["Hello", "Hello"]. This works fine if we know the exact string we’re looking to match, but what about dynamic content or an actual use case?
Here’s a simple example that finds repeated letters in a string:
const str = 'See you later, Alligator! Not so soon baboon!'; const matches = str.match(/([a-z])\1+/gi); console.log('H' + matches.join("")); // "Heelloooo"
Though these are simple examples, the deeper you learn about regular expressions, the more powerful this string method becomes. The simple use of
i for insensitive case allows the match method to highlight more entries.
The match method has 3 modes…
g(global) flag is used for your RegEx, you’ll get all results stored in an array.
gflag used, the first match will return an array with keys/values sharing index of the first matched expression, the full input and then the capturing groups. In other words, the same result as with using
let newYear = "Happy New Year"; let results = newYear.match(/new/i); // [ 'New', index: 6, input: 'Happy New Year', groups: undefined ]
null, or, with the following code, an empty array:
let results = newYear.match(regex) || ;
Join our DigitalOcean community of over a million developers for free! Get help and share knowledge in our Questions & Answers section, find tutorials and tools that will help you grow as a developer and scale your project or business, and subscribe to topics of interest.Sign up
Click below to sign up and get $100 of credit to try our products over 60 days!