Regular Expressions (Regex) in JavaScript - tutorial

Learn the basics of using regular expressions / regex in your JavaScript applications.

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[rossocorsa]

for anyone wondering whats the difference between the + and the * sign, I got the answer for that.
The + sign is true if you have at least 1 match.
The * sign is true if you have at least 0 matches.

[erhxxdt]

At the end you say thank you so much for watching while me must be thankfull to you about your free valuable information.

[VoraciousLime]

Our coding bootcamp never covered regex, this is gold. Thanks so much!

[qdup]

This was a great tutorial man, thanks! I like how you also pointed out a resource for us to use to continue learning and testing it ourselves. Got it is one go and can continue to learn.

[RajeshSays]

Thank you so much for such a good basic explanation of regex.

[sarunasknabikas]

Thanks! Great video helped to get a better idea of what regex is all about.

[atanoomandian]

Thanks for this brief and useful regex tutorial

[sandraofili]

Thank you so much. You just helped me with my project. I was struggling with regular expression

[TheWindsofWonder]

Doing a paid coding bootcamp and they failed to explain this is an understandable way. Thanks freeCodeCamp :P

[harshthechampful]

Brilliant introduction to the topic...very good content for beginners...

[samtrek]

cool it gave me a better understanding of regex

[abdelkarimabouzi]

manager: the coder's name is cody?
me: maybe that's why he became a coder

[ricardofranco]

I’m finding it difficult to understand why/how it is that we iterate through the file names in the loop. I understand when it finds the match prior to the loop. But when you go into the loop, you print out the file name (still understand THAT), but then you set match again to regex.exec(string) and magically it goes to the next grouping without ever modifying string or telling the computer to go to the next word or anything... the string doesn’t change, the regex doesn’t change...wouldn’t match be the same each time you iterate the loop, resulting in an infinite loop?

[turner]

lol literally after understanding what this is its my favorite thing :D

[Captinofthemudslayer]

Question: I have the following regex and text and i would like to match all doubles. However when I try to match them all it skips the 2nd line. How come? Note i am working in bash via mac terminal.
what flags should i used besides -o and -i
([a-z]+) +\1
Paris in the the spring.
The theoretical viewpoint is of little value here.
I view the theoretical viewpoint as being of little value here.
I think that that is often overdone.
This sentence contains contains a doubled word or two two.
Fear fear is a fearful thing.
Writing successful programs requires that the the programmer fully understands the
problem to be solved.

[Timetonut]

this was interesting, but I'm searching for a secret of matching titles in an app. A few song titles are one word, but most have several words. In the app, I'd like for the spaces between words to be either ignored or not have the JavaScript eliminate the space once it was recognized as a match. I'm not sure if the problem is regex or getting JavaScript to play ball.

[jjunit]

Coder Cody or Cody the Coder, im sure you get that a lot lol

[klnzi]

finely thanks very match i understand know

[binhvo]

Thanks for the lecture! Would be nicer if you could provide some "real-life" applications I guess.