I would like to create a regex to validate customer names.
This would be a name like Peter, André, Mary-Anne or Van Rensberg. Asian characters should not be allowed, along with other characters that do not relate to names of this manner.
This will be validated via the HTML5 pattern attribute and then again via PHP as a last resort.
I originally started off with this: [^\p{L}\s0-9]{1,120} which almost applies that I have had in mind, but does not relate exactly to what I am trying to accomplish.
It will basically allow characters like c or é or -, but will not allow spaces and as a side affect allows the input of other special characters like / and %.
Given my very limited knowledge on this subject I thought I would ask this question in order to gain some knowledge from some people that know more than I do.
Thank you for any suggestions of feedback in this regard!
You should start with:
/^([\p{Letter}\p{Latin}]+(\-[\p{Letter}\p{Latin}]+|[\x20\xA0\x{0020}\x{00A0}])?)+$/
and if needed, you can add other scripts, such as:
\p{Hebrew}, \p{Cyrillic}, \p{Georgian}, \p{Greek}, etc.
For more information check "Unicode Regular Expressions".
I suggest you to trim leading/trailing whitespace characters before regex validation.
if you are going to validate if a name is a name, you should try to validate if that name isn't an invalid string with spaces only or a string with a really short lenght.
if you were expecting a regex to validate names maybe this should work
/(^|\s)[A-Za-z\-áéíóúÁÉÍÓÚ]+($|\s)/i
but I insist that the better thing that you can do is to make sure that the name isn't an invalid string, because there is a lot of name and last name with many shapes
Related
I needed a regex to validate wether first and last name were provided corectly or not. Well This is what i came up with:
preg_match('/^[\p{L}]{4,25}[\s][\p{L}]{4,25}$/u', Form::post('name'))
This one works if string contains:
word (4-25 chars long and utf8 chars allowed)
space
word (4-25 chars long and utf8 chars allowed)
which rather is fine, but it seems too much complex for my script
is there a way to convert that regex so it will meet same conditions but has kind of "global" characters range instead, something like this:
(word space word){8,50}
also optionaly it could have second space and third word in case that some foreign person would want to use my site
any help will be appriciated:)
Aside from the fact that name validation is a bad idea in and of itself (see Falsehoods programmers believe about names), and that your regex can be simplified syntactically to
/^\pL{4,25}\s\pL{4,25}$/u
yes, it is possible, but ugly. You would need to use a positive lookahead assertion to make sure that there is only one space, and that it's neither at the end nor at the start of the string:
/^(?=\S+\s\S+$)[\pL\s]{8,50}$/u
If you want to allow more spaces/words, you can use
/^(?=\S+(?:\s\S+)+$)[\pL\s]{8,50}$/u
I would like to create a regex which validates a name of a person. These should be allowed:
Letters (uppercase and lowercase)
-
spaces
This is pretty easy to create a regex for. The problem is that some people also use special characters in their names. For example, assume a user named gûnther or François. There are a lot of characters like û and ç available and it's hard to list all of these.
Is there an easy way to check for correct human names?
Is there an easy way to check for correct human names?
This has been discussed several times. I'm fairly certain that the only thing that people can agree on is that in order to exist a name cannot be a empty string, thus:
^.+$
(Yes, I am aware that this is probably not what OP is looking for. I'm just summarizing earlier Q&As.)
/^\pL[\pL '-]*\z/ should do the trick
The short answer is no, there is no easy way. You have touched on the biggest issue. There are so many special cases of accents and extra things hanging of letters that it will become a mess to deal with. Additionally, the expression with break down to something like this
^[CAPITAL_LETERS][ALL_LETERS_AND_SYMBOLS]*$
That is not that helpful because "Abcd" fits that and you have no way to know if someone is incorrectly entering info into the field or if it was a crazy Hollywood parent that actually named their kid that or something like Sandwich or Umbrella.
^.+$
Checked #jensgram answer, but that regex only accepts all strings, so it doesn't solve problem, because string needs to be name, in this case it can be anything.
^[A-Z][a-z]+$
My regex only accepts string where first char is uppercase and following chars are letters in lowercase. Also looking through other answers, this seems to be shortest regex and also simpliest.
I don't know exactly what you are trying to do (validate user name input?) but basically I would keep it simple - fail the validation if the text contains numbers. And even that's probably pretty shaky.
I had the same problem. First I came up with something like
preg_match("/^[a-zA-Z]{1,}([\s-]*[a-zA-Z\s\'-]*)$/", $name))
but then realized that UTF-8 chars of countries like Sweden, China etc. for example Õ å would not be allowed which was important to my site since it's an international site and don't want to force users not being able to enter their real name.
I though it might be an easier solution instead of trying to figure out how to allow names like O'Malley and Brooks-Schneider and Õsmar (made that one up :) to rather catch chars that you don't want them to enter. For me it was basically to avoid xss JS code being entered. So I use the following regex to filter out all chars that might be harmful.
preg_match("/[~!##\$%\^&\*\(\)=\+\|\[\]\{\};\\:\",\.\<\>\?\/]+/", $name)
That way they can enter any name they want except chars that really aren't part of any name. Hope this might be useful.
First, a brief example, let's say I have this /[0-9]{2}°/ RegEx and this text "24º". The text won't match, obviously ... (?) really, it depends on the font.
Here is my problem, I do not have control on which chars the user uses, so, I need to cover all possibilities in the regex /[0-9]{2}[°º]/, or even better, assure that the text has only the chars I'm expecting °. But I can't just remove the unknown chars otherwise the regex won't work, I need to change it to the chars that looks like it and I'm expecting. I have done this through a little function that maps the "look like" to "what I expect" and change it, the problem is, I have not covered all possibilities, for example, today I found a new -, now we got three of them, just like latex =D - -- --- ,cool , but the regex didn't work.
Does anyone knows how I might solve this?
There is no way to include characters with a "similar appearance" in a regular expression, so basically you can't.
For a specific character, you may have luck with the Unicode specification, which may list some of the most common mistakes, but you have no guarantee. In case of the degree sign, the Unicode code chart lists four similar characters (\u02da, \u030a, \u2070 and \u2218), but not your problematic character, the masculine ordinal indicator.
Unfortunately not in PHP. ASP.NET has unicode character classes that cover things like this, but as you can see here, :So covers too much. Also as it's not PHP doesn't help anyway. :)
In PHP you are going to be limited to selecting the most common character sets and using them.
This should help:
http://unicode.org/charts/charindex.html
There is only one degree symbol. Using something that looks similar is not correct. There are also symbols for degree Fahrenheit and celsius. There are tons of minus signs unfortunately.
Your regular expression will indeed need to list all the characters that you want to accept. If you can't know the string's encoding in advance, you can specify your regular expression to be UTF-8 using the /u modifier in PHP: "/[0-9]{2}[°º]/u" Then you can include all Unicode characters that you want to accept in your character class. You will need to convert the subject string to UTF-8 also before using the regex on it.
I just stumbled into good references for this question:
http://www.unicode.org/Public/6.3.0/ucd/NameAliases.txt
https://docs.python.org/3.4/library/unicodedata.html#unicodedata.normalize
https://www.rfc-editor.org/rfc/rfc3454.html
Ok, if you're looking to pull temp you'll probably need to start with changing a few things first.
temperatures can come in 1 to 3 digits so [0-9]{1,3} (and if someone is actually still alive to put in a four digit temperature then we are all doomed!) may be more accurate for you.
Now the degree signs are the tricky part as you've found out. If you can't control the user (more's the pity), can you just pull whatever comes next?
[0-9]{1,3}.
You might have to beef up the first part though with a little position handling like beginning of the string or end.
You may also exclude all the regular characters you don't want.
[0-9]{1,3}[^a-zA-Z]
That will pick up all the punctuation marks (only one though).
I got a question regarding regexp in general. I'm currently building a register form where you can enter the full name (given name and family name) however I cant use [a-zA-Z] as a validation check because that would exclude everyone with a "foreign" character.
What is the best way to make sure that they don't enter a symbol, in both php and javascript?
Thanks in advance!
The correct solution to this problem (in general) is POSIX character classes. In particular, you should be able to use [:alpha:] (or [:alphanum:]) to do this.
Though why do you want to prevent users from entering their name exactly as they type it? Are you sure you're in a position to tell them exactly what characters are allowed to be in their names?
You first need to conceptually distinguish between a "foreign" character and a "symbol." You may need to clarify here.
Accounting for other languages means accounting for other code pages and that is really beyond the scope of a simple regexp. It can be done, but on a higher level, the codepages have to work.
If you strictly wanted your regexp to fail on punctuation and symbols, you could use [^[:punct:]], but I'm not sure how the [:punct:] POSIX class reacts to some of the weird unicode symbols. This would of course stop some one from putting in "John Smythe-Jones" as their name though (as '-' is a punctuation character), so I would probably advise against using it.
I don’t think that’s a good idea. See How to check real names and surnames - PHP
I don't know how you would account for what is valid or not, and depending on your global reach, you will probably not be able to remove anything without locking out somebody. But a Google search turned this up which may be helpful.
http://nadeausoftware.com/articles/2007/09/php_tip_how_strip_symbol_characters_web_page
You could loop through the input string and use the String.charCodeAt() function to get the integer character code for each character. Set yourself up with a range of acceptable characters and do your comparison.
As noted POSIX character classes are likely the best bet. But the details of their support (and alternatives) vary very much with the details of the specific regex variant.
PHP apparently does support them, but JavaScript does not.
This means for JavaScript you will need to use character ranges: /[\u0400-\u04FF]/ matches any one Cyrillic character. Clearly this will take some writing, but not the XML 1.0 Recommendation (from W3C) includes a listing of a lot of ranges, albeit a few years old now.
One approach might be to have a limited check on the client in JavaScript, and the full check only server side.
here's my problem:
I want to check if a user insert a real name and surname by checking if they have only letters (of any alphabet) and ' or - in PHP.
I've found a solution here (but I don't remember the link) on how to check if a string has only letters:
preg_match('/^[\p{L} ]+$/u',$name)
but I'd like to admit ' and - too. (Charset is UTF8)
Can anyone help me please?
A little off-topic, but what exactly is the point of validating names?
It's not to prevent fraud; if people are trying to give you a fake name, they can easily type a string of random letters.
It's not to prevent mistakes; typing a punctuation character is only one of the many mistakes you could make, and an unlikely one at that.
It's not to prevent code injection; you should be preventing that by properly encoding your outputs, regardless of what characters they contain.
So why do we all do it?
Looks like you just need to modify the regex: [\p{L}' -]+
(International) names can contain many characters: spaces, 's, dashes, normal letters, umlauts, accents, ...
EDIT: The point is: How to be sure all letters (of all languages), dash, ' and space are enough? Are there no names which contain a dot (What about "Dr. No"?), a colon or some char else?
EDIT2: Thanks to the user 'some' probably from Sweden (left a comment) we now know that there is an swedish name 'Andreas J:son Friberg'. Remember the colon!
Depending on the character set you want to permit, you'll just need to make sure that characters you want to support are inside the '[]' portion of the regex. Since the '-' character has special meaning in this context (it creates a range), it needs to be the last item in the list.
The \p{L} means match any character with the property of being a letter. \w has a similar meaning, but also includes the '_' character, which you probably don't want.
preg_match('/^[A-Za-z \'-]+$/i',$name);
Would match most common names, though if you want to support foreign character sets, you'll need more a exotic regex.
This should also do it
/[\w'-]+/gi
if charset is UTF-8, then you have a problem - how are you able to check for Central and Eastern European Latin characters (diacritics) or names in Cyrillic, Chinese or Japanese names? that would be a hell of a regex.
Note that the example you provided does not check to ensure that the user has both a surname and given names, though I would argue that that is how it should be. You shouldn't assume a person has more than one name. I am currently working on a PHP application which deals with people's names in context, and if I have discovered anything it's that you cannot make such assumptions :) Even many non-celebrities have just one name.
Using the Unicode categories as in \p{L} was a good idea, as yes obviously people will have all sorts of characters from other languages in their names. However, as well as \p{L} you will also have to take into account combining marks - ie accents, umlauts etc that people add as extra characters.
So, maybe immediately after \p{L} I'd add \p{Mc}
I'd end up with
preg_match('/^[\pL\p{Mc} \'-]+$/u', $name)