Regular expression in java for validating numbers Chat to horny men without signing up

A subjective criticism is that the code expends a lot of effort checking the length of each component of the domain portion—effort better spent simply trying a domain lookup.Others might appreciate the due diligence paid to checking the domain before executing a DNS lookup on the network.function check_email_address($email) { // First, we check that there's one @ symbol, // and that the lengths are right. ereg("^[^@]{1,64}@[^@]{1,255}$", $email)) { // Email invalid because wrong number of characters // in one section or wrong number of @ symbols.

About 50 people have commented on this solution at the site, including a few corrections that have been incorporated into the original solution.

The only major flaw in the code collectively developed at ILove Jack Daniel's is that it fails to allow for quoted characters, such as \@, in the user name.

It will reject an address with more than one at sign, so that it does not get tripped up splitting the user name and domain parts using .

The Internet Engineering Task Force (IETF) document, RFC 3696, “Application Techniques for Checking and Transformation of Names” by John Klensin, gives several valid e-mail addresses that are rejected by many PHP validation routines. Even assuming a preprocessing step that converts uppercase alphabetic characters to lowercase, the expression rejects addresses with valid characters, such as the slash (/), equal sign (=), exclamation point (! The expression also requires that the highest-level domain component has only two or three characters, thus rejecting valid domains, such as .museum. First, it fails to recognize many valid e-mail address characters, such as percent (%).

The addresses: Abc\@[email protected], customer/[email protected] ! Another favorite regular expression solution is the following: This regular expression rejects all the valid examples in the preceding paragraph. Second, it splits the e-mail address into user name and domain parts at the at sign (@).

One of the more popular regular expressions found in the literature rejects all of them: This regular expression allows only the underscore (_) and hyphen (-) characters, numbers and lowercase alphabetic characters.

It does have the grace to allow uppercase alphabetic characters, and it doesn't make the error of assuming a high-level domain name has only two or three characters. E-mail addresses that contain a quoted at sign, such as Abc\@[email protected] break this code.

Third, it fails to check for host address DNS records.

Hosts with a type A DNS entry will accept e-mail and may not necessarily publish a type MX entry. More than 100 reviewers gave this a four-out-of-five-star rating.

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