Popular:
 Building Resilient Systems on AWS: Learn how to design and implement a resilient, highly available, fault-tolerant infrastructure on AWS.

Remove Multiple New Lines with JavaScript

By  on  

I'm blessed in that lots of people want to guest post on this blog.  It's really flattering and I love seeing writers get a bunch of attention after writing.  My task is converting the blog post, in whatever format it's provided in (HTML, Markdown, PDF, Google Doc, etc.), to HTML for my blog, which can sometimes get messy.  I employ a host of regular expressions to fix these formatting issues.  And the number one problem?  Loads of extra new lines (\n).

The Regular Expression

The regular expression is actually quite simple:

content.replace(/[\r\n]+/g, '\n'); // Just one new line

content.replace(/[\r\n]+/g, '\n\n'); // "document" formatting, more elegant

With the dozens of extra lines gone it's much easier to work with the content!

Request Metrics real user monitoring
Request Metrics real user monitoring
Request Metrics real user monitoring
Request Metrics real user monitoring

Recent Features

  • By
    5 More HTML5 APIs You Didn’t Know Existed

    The HTML5 revolution has provided us some awesome JavaScript and HTML APIs.  Some are APIs we knew we've needed for years, others are cutting edge mobile and desktop helpers.  Regardless of API strength or purpose, anything to help us better do our job is a...

  • By
    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...

Incredible Demos

  • By
    Create a 3D Panorama Image with A-Frame

    In the five years I've been at Mozilla I've seen some awesome projects.  Some of them very popular, some of them very niche, but none of them has inspired me the way the MozVR team's work with WebVR and A-Frame project have. A-Frame is a community project...

  • By
    Style Textarea Resizers

    Modern browsers are nice in that they allow you to style some odd properties.  Heck, one of the most popular posts on this blog is HTML5 Placeholder Styling with CSS, a tiny but useful task.  Did you know you can also restyle the textarea resizer in WebKit...

Discussion

  1. Adam van den Hoven

    David,

    I’m more inclined to use something like:

    content.replace(/[\r\n]\s*/g, '\n'); // Just one new line
content.replace(/[\r\n]\s*/g, '\n\n'); // "document" formatting, more elegant

    Only there always seems to be some extra whitespace between those newlines. If you don’t want to loose the tabs on the next line then this works just as well

    content.replace(/[\r\n]\s*[\r\n]/g, '\n'); // Just one new line
content.replace(/[\r\n]\s*[\r\n]/g, '\n\n'); // "document" formatting, more elegant

Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!