You have three conditions for email validation in your script:

$email =~ m/^[a-z0-9]@[a-z0-9]$/

This will not allow domain extensions, so "u@d" will match, but "u@d.org" will not. Your character sets are not quantified, so they will only match a single character, "user@domain" will no longer match.

If the previous condition matched, the string cannot be empty, so the second condition is superfluous. The last one is actually equivalent to the first, because it matches what the first does and more. Since for it to even be checked the first condition must match, it's virtually the same.

Now for the solution. You need to add quantifiers to the character sets, add a dot (which need to be escaped since it matches anything otherwise) and add another set at the end. The condition could look like this:

$email =~ /^[a-z0-9]+@[a-z0-9]+\.[a-z0-9]+$/

This will not match an empty string, since there needs to be at least one character from every character set, as well as a dot and a @.

If you don't mind allowing uppercase you could simplify it to the form:

$email =~ /^\w+@\w+\.\w+$/

In reply to Re: input - E-mail address - how to check string ? by kroach
in thread input - E-mail address - how to check string ? by zalezny

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