What is the difference between below two regular expressions
(.|[\r\n]){1,1500}
^.{1,1500}$
views:
85answers:
5It does if you specify `RegexOptions.SingleLine`.
cHao
2010-07-20 09:22:44
+4
A:
The first matches up-to-1500 chars, and the second (assuming you haven't set certain regex options) matches a first single line of up-to-1500 chars, with no newlines.
cHao
2010-07-20 09:18:41
...and it (the second one) does so only if either the string contains no newlines at all, or the option `RegexOptions.Multiline` is set because otherwise the `$` means "end of string" instead of "end of line".
Tim Pietzcker
2010-07-20 09:48:59
+2
A:
First expression matches some <= 1500 characters of the file(or other source).
Second expression matches a entire line with charsNumber <= 1500.
. matches any character except \n newline.
serhio
2010-07-20 09:23:13
`.` can match all chars if you specify `RegexOptions.SingleLine`. But even then, there's a subtle difference; the first matches up-to-1500 chars, and the second matches *the first* up-to-1500 chars.
cHao
2010-07-20 09:26:59
I am using this against multi line textbox of ASP.NET.While viewing this in safari i am getting error "Invalid regular expression: regular expression too large"
Nimesh
2010-07-20 09:35:26
first one is giving me error in safari 3.0. What i need to do is that, i need to restrict the user to enter more than 1500 characters and need to display an error message. i am using regular expression validator for this.
Nimesh
2010-07-20 10:03:34
in my text box i should be able to enter not more than 1500 characters. not in a line.
Nimesh
2010-07-20 10:07:06
So you can use `(.|[\n]){1,1500}` (or use `regexOptions.Multiline`). Did you tried in other that Safari browsers?
serhio
2010-07-20 10:11:46
+1
A:
The second one matches the first 1500 characteres of a line IF the line contains 1500 characters or less
rossoft
2010-07-20 09:33:04
+1
A:
If it's for use in a RegularExpressionValidator, you probably want to use this regex:
^[\s\S]{1,1500}$
This is because the regex may be run on either the server (.NET) or the client (JavaScript). In .NET regexes you can use the RegexOptions.Singleline flag (or its inline equivalent, (?s)) to make the dot match newlines, but JavaScript has no such mechanism.
[\s\S] matches any whitespace character or anything that's not a whitespace character--in other words, anything. It's the most popular idiom for matching anything including a newline in JavaScript; it's much, much more efficient than alternation-based approaches like (.|\n).
Note that you'll still need to use a RequiredFieldValidator if you don't want the user to leave the textbox empty.
Alan Moore
2010-07-20 19:42:12