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When users create an account on my site I want to make server validation for emails to not accept every input.
I will send a confirmation, in a way to do a handshake validation.
I am looking for something simple, not the best, but not too simple that doesn't validate anything. I don't know where limitation must be, since any regular expression will not do the correct validation because is not possible to do it with regular expressions.
I'm trying to limit the sintax and visual complexity inherent to regular expressions, because in this case any will be correct.
What regexp can I use to do that?
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Regex : ^(.+)@(.+)$ This one is simplest and only cares about '@' symbol. Before and after '@' symbol, there can be any number of characters. Let's see a quick example to see what I mean.
[a-zA-Z0-9+_. -] matches one character from the English alphabet (both cases), digits, “+”, “_”, “.” and, “-” before the @ symbol. + indicates the repetition of the above-mentioned set of characters one or more times.
With that in mind, to generally validate an email address in JavaScript via Regular Expressions, we translate the rough sketch into a RegExp : let regex = new RegExp('[a-z0-9]+@[a-z]+\.
To validate a RegExp just run it against null (no need to know the data you want to test against upfront). If it returns explicit false ( === false ), it's broken. Otherwise it's valid though it need not match anything. So there's no need to write your own RegExp validator.
It's possible to write a regular expression that only accept email addresses that follow the standards. However, there are some email addresses out there that doesn't strictly follow the standards, but still work.
Here are some simple regular expressions for basic validation:
Contains a @ character:
@ Contains @ and a period somewhere after it:
@.*?\. Has at least one character before the @, before the period and after it:
.+@.+\..+ Has only one @, at least one character before the @, before the period and after it:
^[^@]+@[^@]+\.[^@]+$ User AmoebaMan17 suggests this modification to eliminate whitespace:
^[^@\s]+@[^@\s]+\.[^@\s]+$ And for accepting only one period [external edit: not recommended, does not match valid email adresses]:
^[^@\s]+@[^@\s\.]+\.[^@\.\s]+$ If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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