I need a regular expression to convert US tel number to link

Question

Basically, the input field is just a string. People input their phone number in various formats. I need a regular expression to find and convert those numbers into links.

Answer 1

Afaik, no phone enters the other characters, so why not replace [^0-9] with '' ?

Answer 2

Remove the [] and add \s* (zero or more whitespace characters) around each \-.

Also, you don't need to escape the -. (You can take out the \ from \-)

Explanation: [abcA-Z] is a character group, which matches a, b, c, or any character between A and Z.
It's not what you're trying to do.

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Edits

In response to your updated regex:

• Change [-\.\s] to [-\.\s]+ to match one or more of any of those characters (eg, a - with spaces around it)
• The problem is that \b doesn't match the boundary between a space and a (.

Answer 3

Here's a regex I wrote for finding phone numbers:

(\+?\d[-\.\s]?)?(\(\d{3}\)\s?|\d{3}[-\.\s]?)\d{3}[-\.\s]?\d{4}

It's pretty flexible... allows a variety of formats.

Then, instead of killing yourself trying to replace it w/out spaces using a bunch of back references, instead pass the match to a function and just strip the spaces as you wanted.

C#/.net should have a method that allows a function as the replace argument...

Edit: They call it a `MatchEvaluator. That example uses a delegate, but I'm pretty sure you could use the slightly less verbose

(m) => m.Value.Replace(' ', '')

or something. working from memory here.