Remove Multiple New Lines with JavaScript

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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!

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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
    

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