Allow letters, digits and certain characters and delete the rest [closed] - php

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
This question appears to be off-topic because it lacks sufficient information to diagnose the problem. Describe your problem in more detail or include a minimal example in the question itself.
Closed 9 years ago.
Improve this question
when user submit a form input text
i want it just to allow a-z 0-9 and -_ just this numbers digits and -_
how do i check the input and make it only this inputs allows and delete the rest
Thank You!

$output = preg_replace("/[^a-zA-Z0-9_\-]/", '', $input);

function validate($value){
return preg_match("/^[a-zA-Z0-9_\-]*$/", $value) !== 0;
}
If the return value is false then you have invalid characters, if it true, everything is correct.

$input = preg_replace("/[^0-9a-z\_\-]/i", "", $_POST["myfield"]);
Use regexp.

Related

php - Regular expression to validate this string [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
This question appears to be off-topic because it lacks sufficient information to diagnose the problem. Describe your problem in more detail or include a minimal example in the question itself.
Closed 8 years ago.
Improve this question
What can be the regex to validate the string as below
0000-XXXX-XXXX
four digits at start then hyphen then 4 alphabets then hyphen and then 4 alphabets again.
Thank you.
$string="1234-ABCD-EFGH";
preg_match("~[0-9]{4}-[A-Z]{4}-[A-Z]{4}~", $string, $matches);
print_r($matches);
This code will output the $matches array that contains the match information.
preg_match will return true or false depending on whether the string matched.
If you prefer to also match lower case characters, use this one:
preg_match("~[0-9]{4}-[A-Za-z]{4}-[A-Za-z]{4}~", $string, $matches);

Remove special characters in string [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
This question appears to be off-topic because it lacks sufficient information to diagnose the problem. Describe your problem in more detail or include a minimal example in the question itself.
Closed 8 years ago.
Improve this question
I am currently doing this:
$a = 'some string with special characters';
$a = htmlentities($a);
$a = trim(preg_replace('/&#?[a-z0-9]+;/i', '', $a));
This works but I am wondering if there's a more efficient way to do this?
it contains certain characters like  and I want to remove those.
Try utf8_decode, or more feature-filled:
$output = iconv("UTF-8", "ISO-8859-1//TRANSLIT", $input);
Documentation
The reason I bring this up is because what you are seeing are encoding issues, not "special characters".

PHP - basic phone number validation [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
This question appears to be off-topic because it lacks sufficient information to diagnose the problem. Describe your problem in more detail or include a minimal example in the question itself.
Closed 9 years ago.
Improve this question
I'm trying to validate for UK phone numbers - the specific requirements I have are:
must only consist of digits
the only non-digit characters allowed are space and dash
must begin with a zero
Can anyone suggest a nice and simple regular expression I can use for this?
Try with following regex:
^0([ -]\d+)*\d+$

PHP superscript [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
This question appears to be off-topic because it lacks sufficient information to diagnose the problem. Describe your problem in more detail or include a minimal example in the question itself.
Closed 9 years ago.
Improve this question
Is there any way that I can get o identify characters like(trademark, superscripts, numbers) from text or text file(but these characters are't in HTML code) and replace them using php
Example:
Get from text: ™ replace with PHP: (TM)
Yes, just parse your strings with str_replace.
Note that str_replace can use arrays, so you can replace multiple strings at once:
$text = "Text™®";
$text = str_replace(['™', '®'], ['(TM)', '(R)'], $text);
print $text;

PHP Individual Character validation. Regex? [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Questions asking for code must demonstrate a minimal understanding of the problem being solved. Include attempted solutions, why they didn't work, and the expected results. See also: Stack Overflow question checklist
Closed 9 years ago.
Improve this question
Not terribly familiar with regex, but I'm guessing it's going to make life much easier for my current need.
I need to validate that a string contains the correct sequence of numbers and letters, so that it always follows the format "AA99999A", where A can be any A-Z character and 9 can be any 0-9 character. Other than exploding the string and validating the characters individually, how would the best way to handle this be?
The result can be a simple true / false as I don't need to specify which characters are incorrect
How about:
preg_match('/^[A-Z]{2}\d{5}[A-Z]$/', $string);
You can try this regex:
'/^[A-Z]{2}\d{5}[A-Z]$/i'
PHP's preg_match will do the trick:
$string_to_be_validated = "AB12345C";
if (preg_match("/\A[A-Z]{2}[0-9]{5}[A-Z]{1}\z/", $string_to_be_validated)) echo "valid";
else echo "invalid";
Here you can find more information on this.

Categories