Regular expression prevent non English letters from email-CodePudding

In our project, we use this regular expression to validate emails:

"^([\w-\.] )@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-] \.) ))([a-zA-Z]{2,7}|[0-9]{1,3})(\]?)$"

But it allows non English characters.

For example:

"مستخدم@mail.com"

"userمحمد@mail.com"

"userName@خادم.com"

are valid emails.

How to add another rule to this expression to limit inputs to English letters only?

CodePudding user response：

Can do like this

        string[] StrInputNumber = { "[email protected]", "مستخدم@mail.com'", "userمحمد@mail.com", "userName@خادم.com" };
        Regex ASCIILettersOnly = new Regex(@"^[\P{L}A-Za-z]*$");
        foreach (String item in StrInputNumber) {
        if (ASCIILettersOnly.IsMatch(item)) {
         Console.WriteLine(item   " ==> valid");
        }
        else {
         Console.WriteLine(item   " ==>not valid");
        }
        }

Output

for some basic explanation about regex Click Here

CodePudding user response：

You can use this website to test your regular expression

if you don't need to keep your current expression you can use this one instead: ^[A-Z0-9._% -] @[A-Z0-9.-] .[A-Z]{2,4}$.

I tested it with your examples and it works as you want.