C # Regex for checking phone number

Question

It would be great if someone would help me with Regex for phone numbers. The following are the conditions:

• If + is present, then this must be the first character
• Allowed characters are numbers () - and.
• Minimum 6 rooms and max. 12
• (,) and a space may be on the line
• - should not be the first and last character and should not appear immediately after + if + is present.

Here are some valid numbers:

• [phone]
• [phone]
• 34565464
• 001 [phone]
• +1703.338.6512
• + 934-83227359
• [phone]
• 111-123-4567

Thanks in advance

Answer 1

Try:

^\+?(\d[\d-. ]+)?(\([\d-. ]+\))?[\d-. ]+\d$ 

However, it does not handle counting a number

Answer 2

Not quite the answer to your question, but for those who need to work with phone numbers, there is a Google .NET port libphonenumber : libphonenumber-csharp .