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Created November 29, 2010 10:32
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rfc822 email validation in JS
// See http://rosskendall.com/blog/web/javascript-function-to-check-an-email-address-conforms-to-rfc822
function isEmail(email){
return /^([^\x00-\x20\x22\x28\x29\x2c\x2e\x3a-\x3c\x3e\x40\x5b-\x5d\x7f-\xff]+|\x22([^\x0d\x22\x5c\x80-\xff]|\x5c[\x00-\x7f])*\x22)(\x2e([^\x00-\x20\x22\x28\x29\x2c\x2e\x3a-\x3c\x3e\x40\x5b-\x5d\x7f-\xff]+|\x22([^\x0d\x22\x5c\x80-\xff]|\x5c[\x00-\x7f])*\x22))*\x40([^\x00-\x20\x22\x28\x29\x2c\x2e\x3a-\x3c\x3e\x40\x5b-\x5d\x7f-\xff]+|\x5b([^\x0d\x5b-\x5d\x80-\xff]|\x5c[\x00-\x7f])*\x5d)(\x2e([^\x00-\x20\x22\x28\x29\x2c\x2e\x3a-\x3c\x3e\x40\x5b-\x5d\x7f-\xff]+|\x5b([^\x0d\x5b-\x5d\x80-\xff]|\x5c[\x00-\x7f])*\x5d))*$/.test( email );
}
@jhyland87
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Why is this so different (much shorter) than the other RFC822 patterns ive found? here or here for example? (Granted, those two dont seem to work with JS regex validators such as match or test... so I like yours)

@Leonid-Yeromin
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Passes unicode like: あいうえお@domain.com

@Leonid-Yeromin
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and this:
'email@-domain.com',
'email@domain.web',
'email@111.222.333.44444',

@miniBill
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@Leonid-Yeromin with regards to the first comment: https://tools.ietf.org/html/rfc6531
wrt the second comment, avoiding the number case would overcomplicate the regex, and I don't see a problem with the second case

@curiousdustin
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According to wikipedia, this email should be a valid email.

Dörte@Sörensen.example.com

But the ö appears to make this regex test fail.

Thoughts?

Is this a valid email, but just not valid under RFC 822?

@kapitannwel
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abc@def -said it's a valid email?

@dim2k2006
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@kapitannwel have the same issue with hgdyugf@yahoo (
Any ideas on how to solve it?)

@payalord
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According to wikipedia, this email should be a valid email.

Dörte@Sörensen.example.com

But the ö appears to make this regex test fail.

Thoughts?

Is this a valid email, but just not valid under RFC 822?

This one matched your example email: https://github.com/jackfoxy/FsRegEx/blob/master/tests/Email.Tests/Ultimate.fs

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