Extract a Number from a String with JavaScript
User input from HTML form fields is generally provided to JavaScript as a string. We've lived with that fact for decades but sometimes developers need to extract numbers from that string. There are multiple ways to get those numbers but let's rely on regular expressions to extract those numbers!
To employ a regular expression to get a number within a string, we can use \d+:
const string = "x12345david";
const [match] = string.match(/(\d+)/);
match; // 12345
Regular expressions are capable of really powerful operations within JavaScript; this practice is one of the easier operations. Converting the number using a Number() wrapper will give you the number as a Number type.
![Write Simple, Elegant and Maintainable Media Queries with Sass]()
I spent a few months experimenting with different approaches for writing simple, elegant and maintainable media queries with Sass. Each solution had something that I really liked, but I couldn't find one that covered everything I needed to do, so I ventured into creating my...
![JavaScript Promise API]()
While synchronous code is easier to follow and debug, async is generally better for performance and flexibility. Why "hold up the show" when you can trigger numerous requests at once and then handle them when each is ready? Promises are becoming a big part of the JavaScript world...
![Form Element AJAX Spinner Attachment Using jQuery]()
![Highlighter: A MooTools Search & Highlight Plugin]()
Searching within the page is a major browser functionality, but what if we could code a search box in JavaScript that would do the same thing? I set out to do that using MooTools and ended up with a pretty decent solution.
The MooTools JavaScript Class
The...
the code
string.match(/(\d+)/);assumes that a match is found. If no number is present in the string,string.match(/(\d+)/)will return null, and attempting to destructure null will result in an error