Question

I am trying to detect whether a block of text (from a textarea) contains words that are prefixed with the @sign.

For example in the following text: Hey @John, i just saw @Smith

It will detect John and Smith respectively without the @ symbol. I reckoned something like this would work:

@\w\w+

My question is how do i make javascript filter the text, assuming it is stored in a variable comment?

It should output only the names in the text that are prefixed with @ without the @ symbol.

Regards.

Answer 1

You use the g (global) flag, a capture group, and a loop calling RegExp#exec, like this:

var str = "Hi there @john, it's @mary, my email is [e-mail].";
var re = /\B@(\w+)/g;
var m;

for (m = re.exec(str); m; m = re.exec(str)) {
    console.log("Found: " + m[1]);
}

Output:

Found: john
Found: mary

Live example | source

---

With thanks to @Alex K for the boundary recommendation!