This question already has answers here:
How do I use a Regex to replace non-alphanumeric characters with white space?
(1 answer)
Check for special characters in string
(12 answers)
Closed 3 years ago.
I have to use regex for my password validation that include special characters at least one.
https://en.wikipedia.org/wiki/ASCII
export const passwordValidation = password => {
const regPassword = /^(?=.*?[#?!#$%^&*-]).{8,}$/
return regPassword.test(password)
}
I tried this way but I think this isn't good way.
Is there other way to check all special characters by ascii code except alphanumeric ?
First, you need to define what a "special" character is. Do you mean anything not in the range A-Z (English alphabet)? A-Z and 0-9? Something else? Then you either use a character class listing the ones you want, which is what you've done, or a negated class saying you want something other than what's in the class:
return /^(?=.*?[^a-z0-9]).{8,}$/i.test(password);
// ^---- negated
Related
This question already has answers here:
Regex: match everything but a specific pattern
(6 answers)
Closed 7 months ago.
I need a reqular expression to not match this (/^[a-zA-Z][a-zA-Z0-9]+$/) pattern, where the string needs to start with alphabet followed by number and alphabet, with no special characters.
I tried with (/^?![a-zA-Z]?![a-zA-Z0-9]+$/) and not able to get appropriate answer.
Example:
P123454(Invalid)
PP1234(Invalid)
1245P(valid)
##$124(valid)
Thanks in advance.
^ means start with, So it should start with an alphabetic letter, then any number \d of alphabetic letters a-z with i case insensitive flag.
const check = (str) => {
return /^[^a-z].*/i.test(str)
}
console.log(check('P123454'))
console.log(check('PP1234'))
console.log(check('1245P'))
console.log(check('##$124'))
This regex might be helpful:
/^[^a-zA-Z]+.*$/g
Your every valid input (from the question) should be a match.
Regex 101 Demo
Explanation:
Does not allow string starting with a-zA-Z
Everything after than is allowed (I'm not sure if this is a requirement)
This question already has answers here:
Why this javascript regex doesn't work?
(1 answer)
Match exact string
(3 answers)
Closed 5 years ago.
Regex is the bane of my existence. I've done plenty tutorials, but the rules never stick, and when I look them up they seem to conflict. Anyways enough of my whining. Could someone tell me why this regex doesn't exclude hyphens or brackets:
/^[A-Za-z_][A-Za-z\d_]*/
The way I understand it (or at least what I'm trying to do), the ^ character dictates that the regex should start with the next thing on the list That means the regex should start with [A-Za-z_] or any character a-z and A-Z as well as and underscore _. Then the string can have anything that includes [A-Za-z\d_] which is any alphanumeric character and an underscore. Then I use the * to say that the string can have any number of what was presented previously (any alphanumeric character plus underscore). At no point to I specify a bracket [ or a hyphen -. Why does this expression not exclude these characters
Extra info
I'm verifying this with javascript:
function variableName(name) {
const reg = RegExp("^[A-Za-z_][A-Za-z\d_]*")
return reg.test(name)
}
function variableName("va[riable0") // returns true should be false
It's actually matching the first 2 letters("va"), that's why it's true.
To match the whole phrase, your reg expression should have "$" at the end:
"^[A-Za-z_][A-Za-z\d_]*$"
Your regex matches the part of the string that does not contain the bracket, because your're missing the $ anchor that would (together with ^) force it to match the whole string. Use
const reg = /^[A-Za-z_][A-Za-z\d_]*$/g
// ^
function variableName(name) {
return reg.test(name)
}
console.log(variableName("va[riable0"))
This question already has answers here:
How can I match a pipe character followed by whitespace and another pipe?
(5 answers)
What special characters must be escaped in regular expressions?
(13 answers)
Closed 5 years ago.
I'm using this JS regex text.match(/|(https:.+?path.+?)|/)[1] to get a regex of a URL that is in between pipe | characters but it's not working.
The text is ||https://url.com/path/value|| but I can't seem to extract the URL from it. I need to have path in the middle to identify this particular URL since there are other URLs in the file.
It doesn't have to be a URL that I'm extracting. I mainly would like to know how to extract something from between a pair of characters (| in this case).
You need to escape the pipe ("|") characters:
text.match(/\|(https:.+?path.+?)\|/)[1]
Pipe is a special character that basically means "or". https://www.regular-expressions.info/alternation.html
To grab everything between the two sets of || then you could use this regex:
text.match(/\|\|(.*)\|\|/)
The first part \|\| matches the characters || literally.
The next part (.*)matches any character zero or more and groups the result.
The last part \|\| matches the closing characters || literally.
This question already has answers here:
Regex to find not start and end with dot and allow some special character only not all
(3 answers)
Closed 2 years ago.
I am using following
ng-pattern="/^[a-zA-Z][a-zA-Z0-9._](.*[a-zA-Z0-9])?$/"
The matching String should
not start with a special character,
not end with special character, and
not include consecutive symbols except . (dot) and _ (underscore).
But it is not working.
Please, any suggestion.
Try using the word character class as a start ([\w] = [a-zA-Z0-9_]):
I'm not sure what you mean by consecutive symbols. But this might help:
/^[a-zA-Z]([\w.]*[a-zA-Z0-9])?$/
Maybe, have a look at the JavaScript RegExp Reference
This question already has answers here:
Match only unicode letters
(3 answers)
Closed 4 years ago.
**var pattern = /^[\p{L}0-9 ##'!&(),\[\].+/-]{1,100}$/;** \\first of all I din understand this pattern. someone plz explain it to me\\
if (!pattern.test(Name))
{
alert('Account Name must not contain the given values');
Xrm.Page.getAttribute("name").setValue("");
return false;
}
else
{
return true;
}
when I give this as validation it is throwing error message for all the values I enter. So I need some explanation on the pattern which I think will solve the rest.
In Javascript, the sequence \p{L} (in a character class) has no special meaning; it simply means the letter p or the letter { or the character L or the character }. You're probably getting confused with XRegExp, another library, or another language's (eg Perl, PHP, .NET etc.) implementation of regexps, which support so-called Unicode character categories.
Change
/^[\p{L}0-9 ##'!&(),\[\].+/-]{1,100}$/
to
/^[\p{L}0-9 ##'!&(),\[\].+\/-]{1,100}$/
^^
since you have to escape slashes / since you have defined them to be delimiters.
The meaning of the regex is that your entire string has to be between 1 and 100 characters of the listed characters, numbers and letters.