I have a regex thats working normally (when i tried through online regex checking websitesites).
This should not allow 1234.1234.1234.1234 but while I am using it in asp.net,it is allowing even those values.
Any suggestion?
var ipfilter = new RegExp("(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?$)");
.NET regex differs from JavaScript one immensely. However, in this case, it is a regular problem: the dot must be preceded with a literal backslash, or placed inside a character class. I suggest the latter as it is less error-prone, and you need to add a ^ (start of string) anchor:
var rx = "^(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)[.](25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)[.](25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)[.](25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?$)";
Is the online regex checking website you used testing regex for .NET? .NET regex differs slightly from Javascript regex.
http://refiddle.com/ - you can test against .NET on this by selecting .NET from the regex options drop down on the left.
Related
I need a regex for the ASP.Net (4) Regex Validation control. It needs to be a RegEx validator to support other dynamic behaviors outside the scope of this post..
I was using the following, but it fails if the user enters the % sign following the number (which is a req of my spec):
^(100(?:\.0{1,2})?|0*?\.\d{1,2}|\d{1,2}(?:\.\d{1,2})?)$
I tried adding an atomic group of ^(?>%?) at the end, with no luck, after reading the excellent post
Regular expression greedy match not working as expected
Does anyone have any ideas?
Try this
^(100(?:.0{1,2})?%?|0*?.\d{1,2}%?|\d{1,2}(?:.\d{1,2})?%?)$
try this one instead:
^0*(100(\.00?)?|[0-9]?[0-9](\.[0-9][0-9]?)?)%?$
can someone tell me the javascript regular expression for physical path like
1) User Should enter something like this in the textbox( c://Folder1/) . Maybe in d: or e:
2) But after that acceptable
a) (c://Folder1/Folder2/)
b) (d://Folder1/Folder2/Folder3/abc.txt)
e) (c://Folder1/Folder2/Folder3/abc.txt)
From the examples you've given, something like this should work:
[a-zA-Z]://(\w+/)+
ie:
[a-zA-Z] = a single letter (upper or lower case)
followed by
:// = the characters "://"
followed by:
(\w+/)+ = at least one "something/".
"something/" defined as :
\w+ = at least one word character (ie any alphanumeric), followed by
/ = literal character "/"
Hope this helps - my syntax may be a little off as I'm not fully up to speed on the javascript variant for regex.
Edit: put regex in code tags so it is visible! And tidy up explanation.
This problem is actually trickier than you think. You're trying to validate a path, but paths can be surprisingly hard to properly validate. Are you properly handling UNC network paths, e.g.?
This is known as the canonicalization problem and is part of writing secure code. I suggest checking out some guidance from Microsoft for properly canonicalizing and validating the path in your application. The advantage of canonicalizing your path is that you also implicitly validate its format because the canonical form will be returned from a library call that will only return paths that are potentially valid (properly formatted). This means that you don't have to do any sort of regex validation at all. Just throw your string at the method that canonicalizes the path (Path.GetFullPath() probably) and handle the exception for an invalid path.
Looks like a simple task - get a regex that tests a string for particular length:
^.{1,500}$
But if a string has "\r\n" than the above match always fails!
How should the correct regex look like to accept new line characters as part of the string?
I have a <asp:TextBox TextMode="Multiline"> and use a RegularExpressionValidator to check the length of what user types in.
Thank you,
Andrey
You could use the RegexOptions.Singleline option when validating input. This treats the input as a single line statement, and parses it as such.
Otherwise you could give the following expression a try:
^(.|\s){1,500}$
This should work in multiline inputs.
Can you strip the line breaks before checking the length of the string? That'd be easy to do when validating server-side. (In .net you could use a custom validator for that)
From a UX perspective, though, I'd implement a client-side 'character counter' as well. There's plenty to be found. jQuery has a few options. Then you can implement the custom validator to only run server-side, and then use the character counter as your client-side validation. Much nicer for the user to see how many characters they have left WHILE they are typing.
The inability to set the RegexOptions is screwing you up here. Since this is in a RegularExpressionValidator, you could try setting the options in the regular expression itself.
I think this should work:
(?s)^.{1,500}$
The (?s) part turns on the Singleline option which will allow the dot to match every character including line feeds. For what it's worth, the article here also lists the other RegexOptions and the notation needed to set them as an inline statement.
I have a regex that I am using in an asp.net RegularExpressionValidator to check a TextField.
^(?=.*[a-z])(?=.*\d)(?=.*[A-Z]).{8,}$
The example string I have stumbled on is 'RedCoal1'
Firefox = Matched
IE8 = Matched
Chrome = Matched
IE7 = DOES NOT MATCH
WHY!!!!
The implementation of lookahead in WSH's RegExp as used by IE is just broken. The bug usually pops up in exactly this case, trying to use one regex to verify several things at once.
Plus some older browsers don't support lookahead at all (it wasn't in the original JavaScript spec, though it is now in ECMA-262-3). So all in all it's best to avoid lookahead in browser RegExp.
It would be best to separate out each check (each character class, and length) into manual validation steps.
I'm using an asp.net Web Forms RegularExpressionValidator Control to validate a text field to ensure it contains a series of email addresses separated by semicolons.
What is the proper regex for this task?
I think this one will work:
^([A-Za-z0-9._%+-]+#[A-Za-z0-9.-]+\.[A-Za-z]{2,4}(;|$))+
Breakdown:
[A-Za-z0-9._%+-]+#[A-Za-z0-9.-]+\.[A-Za-z]{2,4} : valid email (from http://www.regular-expressions.info/)
(;|$) : either semicolon or end of string
(...)+ : repeat all one or more times
Make sure you are using case-insensitive matching. Also, this pattern does not allow whitespace between emails or at the start or end of the string.
The 'proper' (aka RFC2822) regex is too complicated. Try something like (\S+#[a-zA-Z0-9-.]+(\s*;\s*|\s*\Z))+
Not perfect but should be there 90% (haven't tried it, so it might need some alteration)
Note: Not too sure about \Z it might be a Perl only thing. Try $ as well if it doesn't work.