What is the regular expression for a 10 digit numeric number (no special characters and no decimal).
Use this regular expression to match ten digits only:
#"^\d{10}$"
To find a sequence of ten consecutive digits anywhere in a string, use:
#"\d{10}"
Note that this will also find the first 10 digits of an 11 digit number. To search anywhere in the string for exactly 10 consecutive digits and not more you can use negative lookarounds:
#"(?<!\d)\d{10}(?!\d)"
Use the following pattern.
^\d{10}$
This works for me:
only 10 digit number is accepted.
^[0-9]{10}$
\d{10}
I believe that should do it
An example of how to implement it:
public bool ValidateSocialSecNumber(string socialSecNumber)
{
//Accepts only 10 digits, no more no less. (Like Mike's answer)
Regex pattern = new Regex(#"(?<!\d)\d{10}(?!\d)");
if(pattern.isMatch(socialSecNumber))
{
//Do something
return true;
}
else
{
return false;
}
}
You could've also done it in another way by e.g. using Match and then wrapping a try-catch block around the pattern matching. However, if a wrong input is given quite often, it's quite expensive to throw an exception. Thus, I prefer the above way, in simple cases at least.
Use this:
\d{10}
I hope it helps.
Related
This question already has an answer here:
Learning Regular Expressions [closed]
(1 answer)
Closed 7 years ago.
I have the following rule:
Don't allow numbers of any sequence with 4 or more 0s at the beginning.
So this number:
0000438967
will fail validation (4 zeros)
But this number:
0004389678 (3 zeros)
Will pass validation.
the reason for this question was I needed verification on whether I was doing it correctly as, when checking in online Regex validators, I was getting mixed verification results. I know it sounds like a simple question but verification from others is important.
thanks
Russ
Unbelievable amount of trial & error answers on this question! The solution is as simple as this:
string number = "0000438967";
bool pass = Regex.IsMatch(number, #"^0{0,3}[1-9]\d*$");
This allows numbers of any length, as long as there is at least one non-zero digit. Replace the last asterisk by {n} or {m,n} to also check length.
Of course, you may want to construct a Regex instance for repeated use.
If you also need the numeric value, you can immediately parse it if pass == true:
int value = Int32.Parse(number);
Of course, depending on the maximum length you want to allow you might need an Int64... but anyway you must provide a maximum length in the regex or the Parse can cause an overflow.
If you must use regular expression, you can use a Negative Lookahead assertion.
^(?!0000)\d+$
Lookarounds are zero-width assertions. They don't consume any characters on the string. The point of zero-width is the validation to see if a regex can or cannot be matched looking ahead or looking back from the current position, without adding them to the overall match.
Example:
Regex.IsMatch("0438967", #"^(?!0000)\d+$"); // True
Regex.IsMatch("004389678", #"^(?!0000)\d+$"); // True
Regex.IsMatch("000438967", #"^(?!0000)\d+$"); // True
Regex.IsMatch("00004389678", #"^(?!0000)\d+$"); // False
Regex.IsMatch("00000438967", #"^(?!0000)\d+$"); // False
Regex.IsMatch("000000438967", #"^(?!0000)\d+$"); // False
Zero to three zeroes followed optionally by a nonzero number followed by any number of numbers:
0{0,3}([1-9][0-9]*)?
It should accept:
000
While rejecting any number with 4+ zeroes at the beginning.
Don't use a lookahead/behind for this as that triggers backtracking.
EDIT: if your matching function does not perform an exact match then you'll need to do:
^0{0,3}([1-9][0-9]*)?$
Please try this..
string myString = "00011111";//Valid
if (Regex.IsMatch(myString, #"^[0-9]{3}[1-9]+$"))
{
Console.WriteLine("Valid");
Console.ReadKey();
}
Assuming you accept no zeros at all and at least one non-zero digit, here is your regex:
string str = "001";
bool passed = Regex.IsMatch(str, #"^0{0,3}[1-9]\d*$");
Explanation: Regex check for 0 to 3 '0's, then for one non-'0' digits and then for zero or more of any digits.
if "000" is acceptable, then negative look-ahead solution from #hwnd is more elegant. I would just use 0{4} instead of 0000.
You can use Regex to find out the string is valid or not
!Regex.Match(str, #"^0000(\d+)", RegexOptions.IgnoreCase).Success
here is working sample rextester
I am looking for a regular expression that validates only positive numbers(integers):
0-999 and first number not 0.
My example not work:
string pattern = #"^\d+$";
How decided positive numbers pattern?
You could force the first digit to be 1-9, and then have any or no digits follow it, like so;
string pattern = #"^[1-9]\d*$";
You can also restrict the amount of digits by putting a numbered constraint on it.
string pattern = #"^[1-9]\d{0,2}$";
The top one will accept any positive integer >0, while the bottom one will accept only 1-999.
How about
#"^[1-9]\d?\d?$"
1-9 followed by 2 optional digits?
use this regular expression ^[1-9]\d{0,2}$
If you just want to validate an input, why not using TryParse?
Regular Expression for positive numbers in C#
double result = 0;
if (Double.TryParse(myString, out result))
{
// Your conditions
if (result > 0 && result < 1000)
{
// Your number
}
}
You can use a lot of useful regex tools online like http://gskinner.com/RegExr/
there's a lot of ready to use examples from which you can start to get your own!
The positive number with two digits after comma:
\d*\,\d\d
What would be the following regular expressions for the following strings?
56AAA71064D6
56AAA7105A25
Would the regular expression change if the numbers rolled over? What I mean by this is that the above numbers happen to contain hexadecimal values and I don't know how the value changes one it reaches F. Using the first one as an example: 56AAA71064D6, if this went up to
56AAA71064F6 and then the following one would become 56AAA7106406, this would create a different regular expression because where a letter was allowed, now their is a digit, so does this make the regular expression even more difficult. Suggestions?
A manufacturer is going to enter a range of serial numbers. The problems are that different manufacturers have different formats for serial numbers (some are just numbers, some are alpha numeric, some contain extra characters like dashes, some contain hexadacimal values which makes it more difficult because I don't know how the roll over to the next serial number). The roll over issue is the biggest problem because the serial numbers are entered as a range like 5A1B - 6F12 and without knowing how the roll over, it seems to me that storing them in the database is not as easy. I was going to have the option of giving the user the option to input the pattern (expression) and storing that in the databse, but if a character or characters changes from a digit to a letter or vice versa, then the regular expression is no longer valid for certain serial numbers.
Also, the above example I gave is with just one case. There are multitude of serial numbers that would contain different expressions.
There's no single regular expression which is "the" expression to match both of those strings. Instead, there are infinitely many which will do so. Here are two options at opposite ends of the spectrum:
(56AAA71064D6)|(56AAA7105A25)
.*
The first will only match those two strings. The second will match anything. Both satisfy all the criteria you've given.
Now, if you specify more criteria, then we'd be able to give a more reasonable idea of the regular expression to provide - and that will drive the answers to the other questions. (At the moment, the only answer that makes sense is "It depends on what regex you use.")
I think you could do it this way for 12 characters. This will search for a 12 character phrase where each of the characters must be a capital (A or B or C or D or E or F or 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9 or 0)
[A-F0-9]{12}
If you're wanting to include the possibility of dashes then do this.
[A-F0-9\-]{12}
Or you're wanting to include the possibility of dashes plus the 12 characters then do this. But that would pick up any 12-15 character item that fit the criteria though.
[A-F0-9\-]{12,15}
Or if it's surrounded by spaces (AAAAHHHh...SO is stripping out my spaces!!!)
[A-F0-9\-]{12}
Or if it's surrounded by tabs
\t[A-F0-9\-]{12}\t
This match a string that contains 12 hexa
[0-9A-F]{12}
Assuming these are all 12-digit hexadecimal numbers, which it looks like they are, the following regex should work:
[0-9A-Fa-f]{12}
Here I'm using a character class to say that I want any digit, OR A-F, OR a-f. As a bonus I'm allowing lowercase letters; if you don't want those just get them out of the regex.
As Jon Skeet and others have said, you really didn't provide enough information, so if you don't like this answer please understand that I was doing the best I can with what information you provided.
So, how about this:
[0-9A-F]{12}
Well it sounds like you're describing a 12 digit hexadecimal number:
^[A-F0-9]{12}$
I'm not sure how to accomplish this with a regular expression (or if I can; I'm new to regex). I have an angle value the user will type in and I'm trying to validate the entry. It is in the form degrees-minutes-seconds. The problem I'm having, is that if the user mistypes the seconds portion, I have to catch that error, but my match for degrees-minutes is a success.
Perhaps the method will explain better:
private Boolean isTextValid(String _angleValue) {
Regex _degreeMatchPattern = new Regex("0*[1-9]");
Regex degreeMinMatchPattern = new Regex("(0*[0-9]-{1}0*[0-9]){1}");
Regex degreeMinSecMatchPattern = new Regex("0*[0-9]-{1}0*[0-9]-{1}0*[0-9]");
Match _degreeMatch, _degreeMinMatch, _degreeMinSecMatch;
_degreeMinSecMatch = degreeMinSecMatchPattern.Match(_angleValue);
if (_degreeMinSecMatch.Success)
return true;
_degreeMinMatch = degreeMinMatchPattern.Match(_angleValue);
if (_degreeMinMatch.Success)
return true;
_degreeMatch = _degreeMatchPattern.Match(_angleValue);
if (_degreeMatch.Success)
return true;
return false;
}
}
I want to check for degrees-minutes if the degrees-minutes-seconds match is unsuccessful, but only if the user didn't enter any seconds data. Can I do this via regex, or do I need to parse the string and evaluate each portion separately? Thanks.
EDIT: Sample data would be 45-23-10 as correct data. The problem is 45-23 is also valid data; the 0 seconds is understood. So if the user types 45-23-1= on accident, the degreeMinMatchPattern regex in my code will match succesfully, even though it is invalid.
Second EDIT: Just to make it clear, the minutes and second portions are both optional. The user can type 45 and that is valid.
You can specify "this part of the pattern must match at least 3 times" using the {m,} syntax. Since there are hyphens between each component, specify the first part separately, and then each hyphen-digit combination can be grouped together after:
`[0-9](-[0-9]){2,}`
You also can shorten [0-9] to \d: \d(-\d){2,}
First off, a character in a regex is matched once by default, so {1} is redundant.
Second, since you can apparently isolate this value (you prompt for just this value, instead of having to look for it in a paragraph of entered data) you should include ^ and $ in your string, to enforce that the string should contain ONLY this pattern.
Try "^\d{1,3}-\d{1,2}(-\d{1,2})?$".
Breaking it down: ^ matches the beginning of the string. \d matches any single decimal character, and then behind that you're specifying {1,3} which will match a set of one to three occurrences of any digit. Then you're looking for one dash, then a similar decimal pattern but only one or two times. The last term is enclosed in parenthesis so we can group the characters. Its form is similar to the first two, then there's a ? which marks the preceding character group as optional. The $ at the end indicates that the input should end. Given this, it will match 222-33-44 or 222-33, but not 222-3344 or 222-33-abc.
Keep in mind there are additional rules you might want to incorporate. For instance, seconds can be expressed as a decimal (if you want a resolution smaller than one second). You would need to optionally expect the decimal point and one or more additional digits. Also, you probably have a maximum degree value; the above regex will match the maximum integer DMS value of 359-59-59, however it will also match 999-99-99 which is not valid. You can limit the maximum value using regex (for example "(3[0-5]\d|[1-2]\d{2}|\d{1,2})" will match any number from 0 to 359, by matching a 3, then 0-5, then 0-9, OR any 3-digit number starting with 1 or 2, OR any two-digit number), but as the example shows the regex will get long and messy, so document it well in code as to what you're doing.
Maybe you would do better to just parse the input out and check is piece separately.
I'm not sure I understand correctly, but I think
(?<degrees>0*[0-9])-?(?<minutes>0*[0-9])(?:-?(?<seconds>0*[0-9]))?$
might work.
But this is quite ambiguous; also I'm wondering why you're only allowing single-digit degree/minute/second values. Please show some examples you do and don't want to match.
Maybe you should to try something like this and test for empty/invalid groups:
Regex degrees = new Regex(
#"(?<degrees>\d+)(?:-(?<minutes>\d+))?(?:-(?<seconds>\d+))?");
string[] samples = new []{ "123", "123-456", "123-456-789" };
foreach (var sample in samples)
{
Match m = degrees.Match(sample);
if(m.Success)
{
string degrees = m.Groups["degrees"].Value;
string minutes = m.Groups["minutes"].Value;
string seconds = m.Groups["seconds"].Value;
Console.WriteLine("{0}°{1}'{2}\"", degrees,
String.IsNullOrEmpty(minutes) ? "0" : minutes,
String.IsNullOrEmpty(seconds) ? "0" : seconds
);
}
}
an 20 - 24 char long alphanumeric string with no spaces and no symbols that has at least 2 digits
AAAAAAAAAAAAAAAAAAAA - not valid
AAAAAA0AAAAAAAAA0AAA - valid
AAAAAA01AAAAAAAAA0AAA - valid
AAAAAA0AAAAAAAAA0AAA# - not valid
I think this is only possible with look-ahead assertion:
^(?=[a-zA-Z\d]{20,24}$)[a-zA-Z]*\d[a-zA-Z]*\d[a-zA-Z\d]*$
The look-ahead assertion ((?=[a-zA-Z\d]{20,24}$)) checks if the string has the expected form (20–24 alphanumeric characters). And the second part ([a-zA-Z]*\d[a-zA-Z]*\d[a-zA-Z\d]*) checks if it contains at least two digits.
I think that this is the simplest pattern: First make a positive lookahead to check that there are at least two digits, then match 20-24 alphanumeric characters:
^(?=.*\d.*\d)[A-Za-z\d]{20,24}$
I'm going to be abstract because this sounds like homework (if it is, please tag it as such).
You can restrict the number of times a pattern matches with {min,max}
You can restrict which characters match with [charlist]
You can impose additional restrictions with what's called zero-width positive lookahead (there's also a negative form). The syntax varies, so check the docs for your environment.
Update your question (& tags) if you need more help.
Gumbo has a correct expression for the requirements.
It could be shortened, but his was more clear and probably faster than the short version.
var rX=/^(?=[a-zA-Z\d]{20,24}$)([a-zA-Z]*\d){2,}/
in JS (not confident enough with C# syntax):
if (str.length >= 20 && str.length <= 24 && /([a-z]*[0-9]){2}[a-z0-9]*/i.test(str)) {
// match found
}
Basically the same idea as Gumbo just a little shorter:
^(?=[\w\d]{20,24}$)[\w]*\d[\w]*\d[\w\d]*$