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.
![Creating Scrolling Parallax Effects with CSS]()
Introduction
For quite a long time now websites with the so called "parallax" effect have been really popular.
In case you have not heard of this effect, it basically includes different layers of images that are moving in different directions or with different speed. This leads to a...
![Camera and Video Control with HTML5]()
Client-side APIs on mobile and desktop devices are quickly providing the same APIs. Of course our mobile devices got access to some of these APIs first, but those APIs are slowly making their way to the desktop. One of those APIs is the getUserMedia API...
![Reverse Element Order with CSS Flexbox]()
CSS is becoming more and more powerful these days, almost to the point where the order of HTML elements output to the page no longer matters from a display standpoint -- CSS lets you do so much that almost any layout, large or small, is possible. Semantics...
![Custom Scrollbars in WebKit]()
Before each of the browser vendors we like was providing unique CSS controls, Internet Explorer was setting the tone. One such example is IE's early implementation of CSS filters. Internet Explorer was also the first browser that allowed developers to, for better or worse, customize...
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