Using regex to validate email and phone fields Qt

Question

I'm trying to use regex to validate email and phone fields (the fields are QLineEdit ).

I'm using the following example:

QString expression = "[1-9]\\d{0,3}";
QRegularExpression rx(expression);
QValidator *validator = new QRegularExpressionValidator(rx, this);

QLineEdit *edit = new QLineEdit(this);
edit->setValidator(validator);

I'm using the following expressions to validate it:

const QString Phone = "/^\+?(\d.*){3,}$/";
const QString Email = "/^.+@.+$/";

These expressions were obtained from this web site: https://projects.lukehaas.me/regexhub/

But it does not work as expected, since it is 'blocking' any input to the email and phone fields.

What regular expressions should I use to validate these fields?

Note that I don't need a much precise validation. I need basically this:

Email : any content, an @ mark, any content, dot, any content. For example: user@email.com or user_123@email.com.br

Phone : any number and the following characters ")(+- ".

Answer 1

You have to remove surrounding / .
You have to fix escaping, using raw string might help:

const QString Phone = R"(^\+?(\d.*){3,}$)";
const QString Email = R"(^.+@.+$)";

There exist more correct regexps to validate phone/mail btw.

Answer 2

I have created the following expressions to validate it:

// ((\\+?(\\d{2}))\\s?)? Matches for example +55 or 55 (optional) and an optional whitespace
// ((\\d{2})|(\\((\\d{2})\\))\\s?)? Matches for example 11 or (11) (optional) and an optional whitespace
// (\\d{3,15}) Matches at least 3 digits and at most 15 digits (required)
// (\\-(\\d{3,15}))? Matches exactly a dash and at least 3 digits and at most 15 digits (optional)
// E.g.: 1234-5678
// E.g.: 11 1234-5678
// E.g.: 11 91234-5678
// E.g.: (11) 1234-5678
// E.g.: +55 11 91234-5678
// E.g.: +55 (11) 91234-5678
// E.g.: 5511912345678
const QString Phone = "^((\\+?(\\d{2}))\\s?)?((\\d{2})|(\\((\\d{2})\\))\\s?)?(\\d{3,15})(\\-(\\d{3,15}))?$";

// [A-Z0-9a-z._-]{1,} Matches one or more occurrences of that digits (including ., _ and -)
// @ Matches exactly one @ character
// (\\.(\\w+)) Matches exactly one dot and one or more word character (e.g. ".com")
// (\\.(\\w+))? Matches one dot and one or more word character (e.g. ".br") (optional)
// E.g.: user@email.com
// E.g.: user_468@email.com.br
const QString Email = "^[A-Z0-9a-z._-]{1,}@(\\w+)(\\.(\\w+))(\\.(\\w+))?(\\.(\\w+))?$";