I have added the following regular expression for validating a mobile phone number:
(^07[1,2,3,4,5,7,8,9][0-9]{7,8}$)
I want to allow the user to enter a # character too and I'm not sure where to fit it in. They may need to enter # character after they have dialed a number, or at the beginning of a number to dial a direct number or an extension.
First, your current regex matches 'numbers' of the format 07,12345678 as well. So you need to change [1,2,3,4,5,7,8,9] to [1-9] (when you have a - between two characters in a character class, it usually means that there's a range)
If you want to accept an optional # character, you can use the ? quantifier which means 0 or 1 times.
^#?07[1-9][0-9]{7,8}#?$
regex101 demo
Except that, as you can see in the demo, it will also match numbers with two hashes; one at the front and one at the end. One option to circumvent this is to use some conditionals (which C# can support).
^(#)?07[1-9][0-9]{7,8}(?(1)|#?)$
regex101 demo
(?(1)|#?) basically means that if the first hash was matched, then nothing more should be matched. Otherwise, if no hash was initially matched, then it can match a hash, if there is one at the end of the number.
In C#, it will be a bit like this:
Regex.Match(myString, #"^(#)?07[1-9][0-9]{7,8}(?(1)|#?)$");
Or you could use a negative lookahead to make sure there's never more than one hash in the number:
^(?!.*#.*#.*$)#?07[1-9][0-9]{7,8}#?$
Related
so I'm developimg a Game with Unity 3D using C#. As first step the user has to enter his personal Code, which consists of 5 pairs, where each pairs has 2 characters/numbers (Im validating the characters & numbers separately). Now what I'm trying to achieve is that after every second character there should appear a minus, like you have after every 4th number, when you enter your credit-card number.
Example: 27-05-AB-CD-EF
So now I tried to use a Regular Expression and its working for the first two letters, but somehow the Regex does see the minus as a character too, and then it adds a minus infinitely often. I tried different versions, where i thought that i just allow letters and numbers, but somehow that doesn't work.
Regex.Replace(codeText, "([A-Za-z0-9][^-]){2}", "$0-");
Any guess what might be doing wrong?
Try with this expression "([A-Za-z0-9]){2}(?!-)" where (?!-) is a Zero-width negative lookahead assertion which in case you don't know is an expression that is matched but isn't part of the match value. So this expression matches two characters that aren't followed by -.
https://www.regular-expressions.info/lookaround.html read this page for more information
I am trying to create regular expression for following type of strings:
combination of the prefix (XI/ YV/ XD/ YQ/ XZ), numerical digits only, and either no ‘Z’ or a ‘Z’ suffix.
For example, XD35Z should pass but XD01HW should not pass.
So far I tried following:
#"XD\d+Z?" - XD35Z passes but unfortunately it also works for XD01HW
#"XD\d+$Z" - XD01HW fails which is what I want but XD35Z also fails
I have also tried #"XD\d{1,}Z"? but it did not work
I need a single regex which will give me appropriate results for both types of strings.
Try this regex:
^(XI|YV|XD|YQ|XZ){1}\d+Z{0,1}$
I'm using quantifying braces to explicitly limit the allowed numbers of each character/group. And the ^ and $ anchors make sure that the regex matches only the whole line (string).
Broken into logical pieces this regex checks
^(XI|YV|XD|YQ|XZ){1} Starts with exactly one of the allowed prefixes
\d+ Is follow by one or more digits
Z{0,1}$ Ends with between 0 and 1 Z
You're misusing the $ which represents the end of the string in the Regex
It should be : #"^XD\d+Z?$" (notice that it appears at the end of the Regex, after the Z?)
The regex following the behaviour you want is:
^(XI|YV|XD|YQ|XZ)\d+Z?$
Explanation:
combination of the prefix (XI/ YV/ XD/ YQ/ XZ)
^(XI|YV|XD|YQ|XZ)
numerical digits only
\d+
‘Z’ or a ‘Z’ suffix
Z?$
I need a regular expression validation expression that will
ALLOW
positive number(0-9)
, and .
DISALLOW
letter(a-z)
any other letter or symbol except . and ,
for example, on my asp.net text box, if I type anything#!#--, the regular expression validation will disallow it, if I type 10.000,50 or 10,000.50 it should allowed.
I've been trying to use this regex:
^\d+(\.\d\d)?$
but my textbox also must allow , symbol and I tried using only integer regex validation, it did disallow if I type string, but it also disallow . and , symbol while it should allow number(0-9) and also . and , symbol
Don't Use \d to match [0-9] in .NET
First off, in .NET, \d will match any digits in any script, such as:
654۳۲١८৮੪૯୫୬१७੩௮௫౫೮൬൪๘໒໕២៧៦᠖
So you really want to be using [0-9]
Incomplete Spec
You say you want to only allow "digits, commas and periods", but I don't think that's the whole spec. That would be ^[0-9,.]+$, and that would match
...,,,
See demo.
Tweaking the Spec
It's hard to guess what you really want to allow: would 10,1,1,1 be acceptable?
We could start with something like this, to get some fairly well-formed strings:
^(?:[0-9]+(?:[.,][0-9]+)?|[1-9][0-9]{0,2}(?:(?:\.[0-9]{3})*|(?:,[0-9]{3})*)(?:\.[0-9]+)?)$
Play with the demo, see what should and shouldn't match... When you are sure about the final spec, we can tweak the regex.
Sample Matches:
0
12
12.123
12,12
12,123,123
12,123,123.12456
12.125.457.22
Sample Non-Matches:
12,
123.
1,1,1,1
Your regex would be,
(?:\d|[,\.])+
OR
^(?:\d|[,\.])+$
It matches one or more numbers or , or . one or more times.
DEMO
Maybe you can use this one (starts with digit, ends with digit):
(\d+[\,\.])*\d+
If you need more sophisticated price Regex you should use:
(?:(?:[1-9]\d?\d?([ \,\.]?\d{3})*)|0)(?:[\.\,]\d+)?
Edit: To make it more reliable (and dont get 00.50) you can add starting and ending symbol check:
(^|\s)(?:(?:[1-9]\d?\d?([ \,\.]?\d{3})*)|0)(?:[\.\,]\d+)($|\s)?
I think the best regex for your condition will be :
^[\d]+(?:,\d+)*(?:\.\d+)?$
this will validate whatever you like
and at the same time:
not validate:
numbers ending in ,
numbers ending in .
numbers having . before comma
numbers having more than one decimal points
check out the demo here : http://regex101.com/r/zI0mJ4
Your format is a bit strange as it is not a standard format.
My first thought was to put a float instead of a string and put a Range validation attribute to avoid negative number.
But because of formatting, not sure it would work.
Another way is the regex, of course.
The one you propose means :
"some numbers then possibly a group formed by a dot and two numbers exactly".
This is not what you exepected.
Strictly fitted your example of a number lower than 100,000.99 one regex could be :
^[0-9]{1-2}[\.,][0-9]{3}([\.,][0-9]{1-2})?$
A more global regex, that accept all positive numbers is the one posted by Avinash Raj : (?:\d|[,\.])+
I'm completely new in this area, I need a regex that follows these rules:
Only numbers and symbols are allowed.
Must start with a number and ends with a number.
Must not contain more than 1 symbol in a row. (for example 123+-4567 is not accepted but 12+345-67 is accepted.
I tried ^[0-9]*[+-*/][0-9]*$ but I think it's a stupid try.
You were close with your attempt. This one should work.
^[0-9]+([+*/-][0-9]+)*$
explanation:
^ matches beginning of the string
[0-9]+ matches 1 or more digits.
[+*/-] matches one from specified symbols
([+*/-][0-9]+)* matches group of symbol followed by at least one digit, repeated 0 or more times
$ matches end of string
We'll build that one from individual parts and then we'll see how we can be smarter about that:
Numbers
\d+
will match an integer. Not terribly fancy, but we need to start somewhere.
Must start with a number and end with a number:
^\d+.*\d+$
Pretty straightforward. We don't know anything about the part in between, though (also the last \d+ will only match a single digit; we might want to fix that eventually).
Only numbers and symbols are allowed. Depending on the complexity of the rest of the regex this might be easier by explicitly spelling it out or using a negative lookahead to make sure there is no non-(number|symbol) somewhere in the string. I'll go for the latter here because we need that again:
(?!.*[^\d+*/-])
Sticking this to the start of the regex makes sure that the regex won't match if there is any non-(number|symbol) character anywhere in the string. Also note that I put the - at the end of the character class. This is because it has a certain special meaning when used between two other characters in a character class.
Must not contain more than one symbol in a row. This is a variation on the one before. We just make sure that there never is more than one symbol by using a negative lookahead to disallow two in sequence:
(?!.*[+/*-]{2})
Putting it all together:
(?!.*[^\d+*/-])(?!.*[+/*-]{2})^\d+.*\d+$
Testing it:
PS Home:\> '123+-4567' -match '(?!.*[^\d+*/-])(?!.*[+/*-]{2})^\d+.*\d+$'
False
PS Home:\> '123-4567' -match '(?!.*[^\d+*/-])(?!.*[+/*-]{2})^\d+.*\d+$'
True
However, I only literally interpreted your rules. If you're trying to match arithmetic expressions that can have several operands and operators in sequence (but without parentheses), then you can approach that problem differently:
Numbers again
\d+
Operators
[+/*-]
A number followed by an operator
\d+[+/*-]
Using grouping and repetition to match a number followed by any number of repetitions of an operator and another number:
\d+([+/*-]\d+)*
Anchoring it so we match the whole string:
^\d+([+/*-]\d+)*$
Generally, for problems where it works, this latter approach works better and leads to more understandable expressions. The former approach has its merits, but most often only in implementing password policies (apart from »cannot repeat any of your previous 30689 passwords«).
We have a requirement to make sure password conforms to the specific strength format (this is configured in web.config). Requirements are that password must contain certain number of capital characters and certain number of non-alphanumeric characters. I want to annotate my Password property with regular expression that validates password to make sure password contains x number of CAPS and y number of non-alpha chars. Please help with regular expression.
Checking multiple conditions like this in a single regex is best accomplished using lookaheads, for example say you want 3 capital characters and 4 non-alpha characters, you could use the following regex:
^(?=(?:.*[A-Z]){3})(?=(?:.*[^a-zA-Z]){4})
Explanation: first, lets think about what a regex would look like that only checks the first condition. To match 3 uppercase characters we can use the following:
(?:.*[A-Z]){3}
We can still check this condition by dropping it inside of a lookahead, which is what the (?=...) does, so now (?=(?:.*[A-Z]){3}) checks this condition without consuming any characters. At this point we can check the second condition using (?:.*[^a-zA-Z]){4}. I put this second condition inside of a lookahead as well so that adding more checks is straightforward.
Note that the current regex won't actually match any characters, it will match the beginning of the string (zero characters) if all conditions match, otherwise the match will fail. If you want it to actually consume characters as well, just add .* to the end.
I found a good article that solves it for me
http://www.zorched.net/2009/05/08/password-strength-validation-with-regular-expressions/