I use a regular expression to on a user-inputted field to make sure that they have entered between 1 and 20 characters.
Here's the code:
$post_validations = array("title" => '/^[[:alnum:][:punct:][:space:]]{1,100}$/');
But whenever a user enters a foreign character, or a special quote character from MS Word (I can't paste it into here, it converts it to a normal quote!) the regex doesn't return true, and it shows an error.
I wondered what would be the best regex to use?
Thanks
If all you want is know that it is between 1 and 20 characters, why not use strlen() ?
$length = strlen($title);
if($length >= 1 and $length <=20)
echo "VALID";
else
echo "Invalid";
[EDIT]: Checking whether aplhanumeric or puctuation:
And if you also want to check whether the string contains any non-printable characters that may cause problem, just use ctype_graph()
if(ctype_graph ($title))
echo "Only alphanumeric or punctuation";
else
echo "Invalid non-printable characters found";
[EDIT 2]:
If you also want the spaces to be validated, just use this:
if(ctype_graph(str_replace(' ', '',$title))
Related
I would like to validate a string with a pattern that can only contain letters (including letters with accents). Here is the code I use and it always returns "nok".
I don't know what I am doing wrong, can you help? thanks
$string = 'é';
if(preg_match('/^[\p{L}]+$/i', $string)){
echo 'ok';
} else{
echo 'nok';
}
Add the UTF-8 modifier flag (u) to your expression:
/^\p{L}+$/ui
There is also no need to wrap \p{L} inside of a character class.
I don't know if this helps anybody that will check this question / thread later. The code below allows only letters, accents and spaces. No symbols or punctuation like .,?/>[-< etc.
<?php
$string = 'États unis and états unis';
if(preg_match('/^[a-zA-Z \p{L}]+$/ui', $string)){
echo 'ok';
} else{
echo 'nok';
}
?>
If you want to add numbers too, just add 0-9 immediately after Z like this a-zA-Z0-9
Then if you are applying this to form validation and you are scared a client/user might just hit spacebar and submit, just use:
if (trim($_POST['forminput']) == "") {... some error message ...}
to reject the submission.
On my website, after a user registers they can change their username at any time. The minimum amount of characters is 6 and max amount is 25.
Here's some of the coding to check the length and remove characters:
$users_new_name = strip_tags($_POST['new_name']);
$new_name = preg_replace("/[^0-9a-zA-Z -]/", "", $users_new_name);
// Check Length
if (ctype_space($new_name)) {
$message = die('<span class="Fail">Error: Name Must Be At least 6 Characters Long!</i></span>');
}
if(strlen($new_name) < 6) {
$message = die('<span class="Fail">Error: Name Must Be At least 6 Characters Long!</i></span>');
}
if(strlen($new_name) > 25) {
$message = die('<span class="Fail">Error: Name Can\'t Be More Than 25 Characters Long!</i></span>');
}
The issue I'm having is if you type in 5 spaces and then a letter or number, There new name will be that letter or number; Or if you type in a letter or number then 5 spaces. How could I prevent this from happening?
Here's a screenshot of the example
I do not understand why tags would be in a POST.
Spaces becomes a non-issue if you change:
$users_new_name = strip_tags($_POST['new_name']);
To
$users_new_name = trim(strip_tags($_POST['new_name']));
Or ideally (strip tags is unnecessary):
$users_new_name = trim($_POST['new_name']);
Change the RegEx expression to /[^0-9a-zA-Z]/ to eliminate spaces and dashes.
It sounds like you need trim() to trim any spaces from the username. See http://php.net/trim
ltrim() will trim any leading spaces. rtrim() will trim any spaces at the end of the string.
This is fairly simple and it's something I've had to deal with on systems before.
If you make the first thing you call, this preg_replace, the rest of you code should catch it;
$name = preg_replace('~[\s]+~', '', $name);
This simply checks if there is a space, or more than one, then replaces with a single space.
So " l" would return " l" - failing your 5 character minimum.
Use trim() around this and you should have it working to something acceptable (Depending on your definition of acceptable - worked in my use-case)
I have this code in preg_match
if (preg_match("/(for+\([\w\-]+\;[\w\-]+\;[\w\-]+\){)/",$email))
{
$message = "Valid input";
}
else
$message ="Invalid Input";
if the user will input for(aw;aw;aw){
if will output Valid input
but if the user will put a space like for (awd ; awd; awd) {
it will output invalid input..
my problem is how can i bypass space or remove space without using explode to my string..
need help..
You can match a space like any other character. So for example, you can just add spaces where needed, like below:
if (preg_match("/(for+ *\([\w\-]+ *\; *[\w\-]+ *\; *[\w\-]+\) *{)/",$email))
However, for+ matches 1 or more literal r's so would also match positively on forrrr, so just using for might be more appropriate there.
For my PHP script I have this code:
if (!preg_match("/[^A-Za-z]/", $usersurname))
$usersurname_valid = 1;
This worked untill I realized a surname can be two or more words... doh.
Anyone can tell me how to write this code if I want to allow 1 space between two worlds? For example:
Jan Klaas is now wrong and Jan Klaas should be allowed, also Jan Klaas Martijn and so on should be allowed.
Even better would be a preg replace, to replace two or more spaces with 1, so when you write: Jan(space)(space)Klaas or Jan(space)(space)(space)(space)Klaas, it would return Jan(space)Klaas.
I searched around for a while but somehow I just can't get this space matching to work..
PS: When I got this working, I will apply this for the mid and last name too ofcourse.
===========================================
EDIT: After you helping me out, I re-wrote my code to:
// validate usersurname
$usersurname = preg_replace("/\s{2,}/"," ", $usersurname);
if (!preg_match("/^[A-Za-z]+(\s[A-Za-z]+)*$/",$usersurname))
$usersurname_valid = 1;
// validate usermidname
$usermidname = preg_replace("/\s{2,}/"," ", $usermidname);
if (!preg_match("/^[A-Za-z]+(\s[A-Za-z]+)*$/",$usermidname))
$usermidname_valid = 1;
// validate userforename
$userforename = preg_replace("/\s{2,}/"," ", $userforename);
if (!preg_match("/^[A-Za-z]+(\s[A-Za-z]+)*$/",$userforename))
$userforename_valid = 1;
and the error notifications
elseif ($usersurname_valid !=1)
echo ("<p id='notification'>Only alphabetic character are allowed for the last name. $usersurname $usermidname $userforename</p>");
// usermidname character validation
elseif ($usermidname_valid !=1)
echo ("<p id='notification'>Only alphabetic character are allowed for the middle name. $usersurname $usermidname $userforename</p>");
// userforename character validation
elseif ($userforename_valid !=1)
echo ("<p id='notification'>Only alphabetic character are allowed for the (EDIT) first name. $usersurname $usermidname $userforename</p>");
Replacing the spaces are working well and I need this preg_match to check on on A-Za-z + space. I think in this case it doesn't matter if it's matching more than 1 spaces because it's replaced anyway, right?
EDIT:
Solution for my case:
$usersurname = preg_replace("/\s{2,}/"," ", $usersurname);
if (!preg_match("/[^A-Za-z ]/", $usersurname))
This does the work. Thanks for helping out, J0HN
Well, solving the problem you have in mind:
if (!preg_match("/^[A-Za-z]+(\s[A-Za-z]+)*$/",$usersurname)) { ... }
But, well, it's just a part of the solution, and it's not bulletproof. Look at the list of common mistakes when handling names.
So, you'd better to re-think on your validation approach.
Replacing the multiple spaces is simpler to achieve as a separate instruction, something like
$processed_usersurname = preg_replace("/\s{2,}/"," ", $usersurname);
This will match and replace any two or more consequent whitespace characters (space, tab, linebreak and carriage return) to single space
I would like to validate a string with a pattern that can only contain letters (including letters with accents). Here is the code I use and it always returns "nok".
I don't know what I am doing wrong, can you help? thanks
$string = 'é';
if(preg_match('/^[\p{L}]+$/i', $string)){
echo 'ok';
} else{
echo 'nok';
}
Add the UTF-8 modifier flag (u) to your expression:
/^\p{L}+$/ui
There is also no need to wrap \p{L} inside of a character class.
I don't know if this helps anybody that will check this question / thread later. The code below allows only letters, accents and spaces. No symbols or punctuation like .,?/>[-< etc.
<?php
$string = 'États unis and états unis';
if(preg_match('/^[a-zA-Z \p{L}]+$/ui', $string)){
echo 'ok';
} else{
echo 'nok';
}
?>
If you want to add numbers too, just add 0-9 immediately after Z like this a-zA-Z0-9
Then if you are applying this to form validation and you are scared a client/user might just hit spacebar and submit, just use:
if (trim($_POST['forminput']) == "") {... some error message ...}
to reject the submission.