This php code is not catching numeric characters or symbols as it should.
$firstname = check_input($_POST['firstname'], "Please enter your first name");
$firstname = ucwords($firstname);
if (!preg_match("/^[a-zA-Z ]*$/",$firstname)) {
show_error("Name should have only alpha characters and white space");
}
For example, the results should be Geronimo. If ge5on*mo is entered, that's what gets returned.
Any suggestions?
Well, no full test cases in your example. So I will try to walk blindly in the dark. At first your expression is flawed, because it can capture just empty spaces without any name. Second - it doesn't captures unicode characters. I would start with such expression for name capture :
^(?:\p{Lu}\p{Ll}+[-\h]?){1,}$
Explanation:
^(?:
\p{Lu} // first letter in name must be in upper-case
\p{Ll}+ // after that goes at least 1 non-upper case letter
[-\h]? // we allow separators between names
){1,} // human can have multiple names (at least 1)
$
I need a regular expression with condition:
min 6 characters, max 50 characters
must contain 1 letter
must contain 1 number
may contain special characters like !##$%^&*()_+
Currently I have pattern: (?!^[0-9]*$)(?!^[a-zA-Z]*$)^([a-zA-Z0-9]{6,50})$
However it doesn't allow special characters, does anybody have a good regex for that?
Thanks
Perhaps a single regex could be used, but that makes it hard to give the user feedback for which rule they aren't following. A more traditional approach like this gives you feedback that you can use in the UI to tell the user what pwd rule is not being met:
function checkPwd(str) {
if (str.length < 6) {
return("too_short");
} else if (str.length > 50) {
return("too_long");
} else if (str.search(/\d/) == -1) {
return("no_num");
} else if (str.search(/[a-zA-Z]/) == -1) {
return("no_letter");
} else if (str.search(/[^a-zA-Z0-9\!\#\#\$\%\^\&\*\(\)\_\+]/) != -1) {
return("bad_char");
}
return("ok");
}
following jfriend00 answer i wrote this fiddle to test his solution with some little changes to make it more visual:
http://jsfiddle.net/9RB49/1/
and this is the code:
checkPwd = function() {
var str = document.getElementById('pass').value;
if (str.length < 6) {
alert("too_short");
return("too_short");
} else if (str.length > 50) {
alert("too_long");
return("too_long");
} else if (str.search(/\d/) == -1) {
alert("no_num");
return("no_num");
} else if (str.search(/[a-zA-Z]/) == -1) {
alert("no_letter");
return("no_letter");
} else if (str.search(/[^a-zA-Z0-9\!\#\#\$\%\^\&\*\(\)\_\+\.\,\;\:]/) != -1) {
alert("bad_char");
return("bad_char");
}
alert("oukey!!");
return("ok");
}
btw, its working like a charm! ;)
best regards and thanks to jfriend00 of course!
Check a password between 7 to 16 characters which contain only characters, numeric digits, underscore and first character must be a letter-
/^[A-Za-z]\w{7,14}$/
Check a password between 6 to 20 characters which contain at least one numeric digit, one uppercase, and one lowercase letter
/^(?=.\d)(?=.[a-z])(?=.*[A-Z]).{6,20}$/
Check a password between 7 to 15 characters which contain at least one numeric digit and a special character
/^(?=.[0-9])(?=.[!##$%^&])[a-zA-Z0-9!##$%^&]{7,15}$/
Check a password between 8 to 15 characters which contain at least one lowercase letter, one uppercase letter, one numeric digit, and one special character
/^(?=.\d)(?=.[a-z])(?=.[A-Z])(?=.[^a-zA-Z0-9])(?!.*\s).{8,15}$/
I hope this will help someone. For more please check this article and this site regexr.com
A more elegant and self-contained regex to match these (common) password requirements is:
^(?=.*[A-Za-z])(?=.*\\d)[A-Za-z\\d^a-zA-Z0-9].{5,50}$
The elegant touch here is that you don't have to hard-code symbols such as $ # # etc.
To accept all the symbols, you are simply saying: "accept also all the not alphanumeric characters and not numbers".
Min and Max number of characters requirement
The final part of the regex {5,50} is the min and max number of characters, if the password is less than 6 or more than 50 characters entered the regex returns a non match.
I have a regex, but it's a bit tricky.
^(?:(?<Numbers>[0-9]{1})|(?<Alpha>[a-zA-Z]{1})|(?<Special>[^a-zA-Z0-9]{1})){6,50}$
Let me explain it and how to check if the tested password is correct:
There are three named groups in the regex.
1) "Numbers": will match a single number in the string.
2) "Alpha": will match a single character from "a" to "z" or "A" to "Z"
3) "Special": will match a single character not being "Alpha" or "Numbers"
Those three named groups are grouped in an alternative group, and {6,50} advises regex machine to capture at least 6 of those groups mentiond above, but not more than 50.
To ensure a correct password is entered you have to check if there is a match, and after that, if the matched groups are capture as much as you desired. I'm a C# developer and don't know, how it works in javascript, but in C# you would have to check:
match.Groups["Numbers"].Captures.Count > 1
Hopefully it works the same in javascript! Good luck!
I use this
export const validatePassword = password => {
const re = /^(?=.*[A-Za-z])(?=.*\d)[a-zA-Z0-9!##$%^&*()~¥=_+}{":;'?/>.<,`\-\|\[\]]{6,50}$/
return re.test(password)
}
DEMO https://jsfiddle.net/ssuryar/bjuhkt09/
Onkeypress the function triggerred.
HTML
<form>
<input type="text" name="testpwd" id="testpwd" class="form=control" onkeyup="checksPassword(this.value)"/>
<input type="submit" value="Submit" /><br />
<span class="error_message spassword_error" style="display: none;">Enter minimum 8 chars with atleast 1 number, lower, upper & special(##$%&!-_&) char.</span>
</form>
Script
function checksPassword(password){
var pattern = /^.*(?=.{8,20})(?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[##$%&!-_]).*$/;
if(!pattern.test(password)) {
$(".spassword_error").show();
}else
{
$(".spassword_error").hide();
}
}
International UTF-8
None of the solutions here allow international letters, i.e. éÉöÖæÆóÓúÚáÁ, but are mainly focused on the english alphabet.
The following regEx uses unicode, UTF-8, to recognise upper and lower case and thus, allow international characters:
// Match uppercase, lowercase, digit or #$!%*?& and make sure the length is 6 to 50 in length
const pwdFilter = /^(?=.*\p{Ll})(?=.*\p{Lu})(?=.*[\d|##$!%*?&])[\p{L}\d##$!%*?&]{6,50}$/gmu
if (!pwdFilter.test(pwd)) {
// Show error that password has to be adjusted to match criteria
}
This regEx
/^(?=.*\p{Ll})(?=.*\p{Lu})(?=.*[\d|##$!%*?&])[\p{L}\d##$!%*?&]{6,50}$/gmu
checks if an uppercase, lowercase, digit or #$!%*?& are used in the password. It also limits the length to be 6 minimum and maximum 50 (note that the length of 😀🇺🇸🇪🇸🧑💻 emojis counts as more than one character in the length).
The u in the end, tells it to use UTF-8.
First, we should make the assumption that passwords are always hashed (right? always hashed, right?). That means we should not specify the exact characters allowed (as per the 4th bullet). Rather, any characters should be accepted, and then validate on minimum length and complexity (must contain a letter and a number, for example). And since it will definitely be hashed, we have no concerns over a max length, and should be able to eliminate that as a requirement.
I agree that often this won't be done as a single regex but rather a series of small regex to validate against because we may want to indicate to the user what they need to update, rather than just rejecting outright as an invalid password. Here's some options:
As discussed above - 1 number, 1 letter (upper or lower case) and min 8 char. Added a second option that disallows leading/trailing spaces (avoid potential issues with pasting with extra white space, for example).
^(?=.*\d)(?=.*[a-zA-Z]).{8,}$
^(?=.*\d)(?=.*[a-zA-Z])\S.{6,}\S$
Lastly, if you want to require 1 number and both 1 uppercase and 1 lowercase letter, something like this would work (with or without allowing leading/trailing spaces)
^(?=.*\d)(?=.*[a-z])(?=.*[A-Z]).{8,}$
^(?=.*\d)(?=.*[a-z])(?=.*[A-Z])\S.{6,}\S$
Lastly as requested in the original post (again, don't do this, please try and push back on the requirements!!) - 1 number, 1 letter (upper or lower case), 1 special char (in list) and min 8 char, max 50 char. Both with/without allowing leading/trailing spaces, note the min/max change to account for the 2 non-whitespace characters specified.
^(?=.*\d)(?=.*[a-zA-Z])(?=.*[!##$%^&*()_+]).{8,50}$
^(?=.*\d)(?=.*[a-zA-Z])(?=.*[!##$%^&*()_+])\S.{6,48}\S$
Bonus - separated out is pretty simple, just test against each of the following and show the appropriate error in turn:
/^.{8,}$/ // at least 8 char; ( /^.{8,50}$/ if you must add a max)
/[A-Za-z]/ // one letter
/[A-Z]/ // (optional) - one uppercase letter
/[a-z]/ // (optional) - one lowercase letter
/\d/ // one number
/^\S+.*\S+$/ // (optional) first and last character are non-whitespace)
Note, in these regexes, the char set for a letter is the standard English 26 character alphabet without any accented characters. But my hope is this has enough variations so folks can adapt from here as needed.
// more secure regex password must be :
// more than 8 chars
// at least one number
// at least one special character
const PASSWORD_REGEX_3 = /^(?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[!##$%^&*]).{8,}$/;
I have to have a regular expression that contains at least one lowercase letter, uppercase letter, number, and symbol (non letter or number). I must also contain no spaces and must be between 8 and 16 characters long. I must use the 0-9a-zA-z Expression. I cannot use any other to represent the letters and numbers.
I have run into a few problems which I hope you guys can help me with. I will seperate the issues with line.
1) Quantifier not working
<?php
$Password = "Fondulious16";
echo preg_match("/[0-9a-zA-Z]{8,16}[^\s]/", $Password);
?>
Now, It does return 0 if i change the password to go below 8 chacters. But it still returns a 1 if I go above 16 characters.
2) Requirements not working
If I change the brackets to parenthesis it always returns 0 and I can remove the capital letter. So i need to make it to where It will require a capital, lower case, and number. I've tried adding in the + symbol but to no avail:
<?php
$Password = "Fondulious16";
echo preg_match("/[0-9+a-z+A-Z+]{8,16}[^\s]/", $Password);
?>
This did nothing, and nothing changed when I changed the password to something like "fondulious".
<?php
$Password = "Fondulious16";
echo preg_match("/(0-9a-zA-Z){8,16}[^\s]/", $Password);
?>
This always returns 0.
Thanks in advance for any help.
Your problem in both cases is the fact that [^\s] is essentially the same as \S; in short: Anything but a space character.
So this last part of the expression will match anything as long as there is indeed at least some character (i.e. not the end of the string).
Also you can't use the + quantifier within one selection/range ([...]). It's just a normal character in there and by default the quantifier following will be able to pick any valid character as often as necessary (there's no easy way to force the elements to be unique anyway).
So, to fix your problem, you should use the following regular expression:
<?php
$password = "Fondulious16";
echo preg_match('/^\w{8,16}$/', $password);
?>
Here's a short explanation of the elements:
^ will match the beginning of the string.
\w will match any alphanumerical character plus underscores (essentially [a-z0-9_], but case-insensitive).
{8,16} is a quantifier "8 to 16 times" as you used it.
$ will match the end of the string.
If you don't want underscores to be valid, you can use the following variant.
<?php
$password = "Fondulious16";
echo preg_match('/^[0-9a-z]{8,16}$/i', $password);
?>
You might have noticed that I didn't list uppercase characters. Instead, I've used the modifier i after the trailing delimiter (/i) which will tell the algorithm to ignore the case of all characters when trying to match them.
Although it's important to note that this check will not force the user to use lowercase and uppercase characters as well as numbers. It will only check whether the user used any other characters (like punctuation or spaces) as well as the length!
To force the user to use all those things in addition, you can use the following check:
<?php
$password = "Fondulious16";
echo preg_match('/[A-Z]/', $password) // at least one uppercase character
&& preg_match('/[a-z]/', $password) // at least one lowercase character
&& preg_match('/\d/', $password); // at least one number
?>
If you'd like to do these checks and you want to verify the length as well, then you can use the following expression to look for illegal characters (and a simple string length check to ensure the length is fine):
<?php
$password = "Fondulious16";
echo ($pwlen = strlen($password)) >= 8 && $pwlen <= 16 // has the proper length
&& preg_match('/[A-Z]/', $password) // at least one uppercase character
&& preg_match('/[a-z]/', $password) // at least one lowercase character
&& preg_match('/\d/', $password) // at least one number
&& !preg_match('/[^a-z\d]/i', $password); // no forbidden character
?>
Please look at the below
example
if (!preg_match('/([a-z]{1,})/', $value)) {
// atleast one lowercase letter
}
if (!preg_match('/([A-Z]{1,})/', $value)) {
// atleast one uppercase letter
}
if (!preg_match('/([\d]{1,})/', $value)) {
// altelast one digit
}
if (strlen($value) < 8) {
// atleast 8 characters length
}
I am creating a password validation tool, and one of the requirements I'd like is to prevent the user from having too many letters in a row. Any letters, including capital letters, cannot be repeated in a sequence of 3 or more times.
My approach has been to move through the password string with a for loop, and embedding a few checks using regex within that. I can't seem to get the logic to work, and it's probably something simple. Here is one of my (many) failed attempts at cracking this problem:
$seqLetterCounter = 0;
for($i=0; $i < strlen($password); ++$i) {
if($password{$i} == '/([a-zA-Z])/') {
$seqLetterCounter++;
}
if($seqLetterCounter > $this->maxSeqLetters){
$this->errors[6] = 'You have used too many sequential letters in your password. The maximum allowed is ' . $this->maxSeqLetters . '.';
}
if($password{$i} == '/([^a-zA-Z])/') {
$seqLetterCounter = 0;
}
}
$password - a posted value from a form.
$maxSeqLetters - a protected variable that holds an integer value, defined by the user.
errors[] - an array that is used to determine if the password has failed any of the various checks.
Anyone have some pointers?
Fairly simple with a regex:
if (preg_match('/(\w)\1{2,}/', $password)) {
die("3+ repeated chars not allowed");
}
Search for a character (\w), store it (()), then see if that same character comes immediately afterwards (\1) two or more times {2,}.
ok... so if consecutive sets of 3+ letters or numbers are out, then try
/([a-z]{3,}|[0-9]{3,})/i
for the regex instead. Search for any letters ([a-z]) OR (|) numbers ([0-9]), which occur 3 or more times ({3,}), and do the match in a case-insensitive manner (i), so you don't have to worry about aAa breaking the match.
I'm newest and happy to be here in Stackoverflow. I am following this website since a long time.
I have an input/text field. (e.g. "Insert your name")
The script starts the following controls when the user sends data:
1) Control whether the field is empty or not.
2) Control whether the field goes over maximum characters allowed.
3) Control whether the field contain a wrong matched preg_match regex. (e.g. it contains numbers instead of only letters - without symbols and accents -).
The question is: why if i put this characters "w/", the script doesn't make the control? And it seems like the string bypass controls?
Hello to all guys and sorry if I'm late with the answer (and also for the non-code posted ^^).
Now, talking about my problem. I checked that the problem is on ONLY if I work offline (I use EasyPhp 5.3.6.1). Otherwise the regEx tested online is ok.
This is the code I use to obtain only what I said above:
if (!preg_match('/^[a-zA-Z]+[ ]?[a-zA-Z]+$/', $name)) {
echo "Error";
}
As you can see, this code match:
A string that start (and finish) with only letters;
A string with only 0 or 1 empty space (for persons who has two name, i.e.: Anna Maria);
...right?!
(Please correct me if I am wrong)
Thanks to all!
Wart
My reading of the requirements is
Only letters (upper or lower) can be provided.
Something must be provided (i.e. a non-zero length string).
There is a maximum length.
The code below checks this in a very simple manner and just echos any errors it finds; you probably want to do something more useful when you detect an error.
<?php
$max = 10;
$string = 'w/';
// Check only letters; the regex searches for anything that isn't a plain letter
if (preg_match('/[^a-zA-Z]/', $string)){
echo 'only letters are allowed';
}
// Check a value is provided
$len = strlen($string);
if ($len == 0) {
echo 'you must provide a value';
}
// Check the string is long to long
if ($len > $max) {
echo 'the value cannot be longer than ' . $max;
}
You can also try this:
if (preg_match('/^[a-z0-9]{1,12}/im', $subject)) {
\\ match
}
The above will only match similar to #genesis' post, but will only match if the $subject is between and including 1 - 12 characters long. The regex is also case insensitive.
It works fine.
<?php
$string = '\with';
if (preg_match('~[^0-9a-z]~i', $string)){
echo "only a-Z0-9 is allowed"; //true
}
http://sandbox.phpcode.eu/g/18535/3
You have to make sure you don't put user input into your regex, because that would mean you'll probably check something wrong.