👀 Views: 1651 💬 Answers: 1 📅 Created: 2025-06-08

regex javascript string-manipulation JavaScript

I've spent hours debugging this and I've been working on a JavaScript function that needs to extract hexadecimal color codes from a string. I initially believed my regex pattern would work seamlessly, but I'm working with unexpected behavior when it comes to certain edge cases. My current regex pattern looks like this: `#(?:[0-9a-fA-F]{3}|[0-9a-fA-F]{6})`. This pattern seems to work fine for most inputs, capturing colors like `#ff5733` and `#abc`, but it fails to capture cases where there's whitespace or newline characters around the hex codes, such as in the string `"Background: #abc; Color: #ff5733;"`. In this case, it returns an empty match. I've tried adding optional whitespace handling by modifying my regex to `\s*#(?:[0-9a-fA-F]{3}|[0-9a-fA-F]{6})\s*`, but this doesn't seem to fix the scenario. Here’s a snippet of the code I'm using: ```javascript const extractHexColors = (input) => { const regex = /\s*#(?:[0-9a-fA-F]{3}|[0-9a-fA-F]{6})\s*/g; return input.match(regex); }; const inputString = 'Background: #abc; Color: #ff5733;'; console.log(extractHexColors(inputString)); // Expected: ['#abc', '#ff5733'] ``` However, this outputs `null` for strings with just one hex code surrounded by spaces. I even tried using the `trim()` method on the input string, but that didn’t lead to any improvements. What am I missing here? Is it that my regex isn't accounting for certain scenarios, or is there something wrong with how I'm applying it? Any suggestions for refining my regex to ensure it captures all valid hex codes, including those that may have whitespace around them would be greatly appreciated! What's the best practice here?