473,569 Members | 2,844 Online
Bytes | Software Development & Data Engineering Community
+ Post

Home Posts Topics Members FAQ

regexp @ operator

I understand that the following would split the line in words space
separated: string[] words = Regex.Split(tex t, @"\W+"); Why do we need
@ before regular expression?
Thanks
Nov 3 '08 #1
5 2149
In C# the backslash (\) serves for escaping characters, and when you want to
include the literal backslash you have to escape it in one of two ways:

1) using the @ prefix which escapes all backslashes, or
2) by escaping the backslash using another one, e.g. "\\W+"

I personally prefer and recommend the @ prefix because I don't have to do it
for further slashes.
--
Stanimir Stoyanov
http://stoyanoff.info

"puzzlecrac ker" <ir*********@gm ail.comwrote in message
news:9d******** *************** ***********@o40 g2000prn.google groups.com...
>I understand that the following would split the line in words space
separated: string[] words = Regex.Split(tex t, @"\W+"); Why do we need
@ before regular expression?
Thanks
Nov 3 '08 #2
On Nov 3, 9:09*am, "Stanimir Stoyanov" <stoya...@REMOV ETHIS.live.com>
wrote:
In C# the backslash (\) serves for escaping characters, and when you wantto
include the literal backslash you have to escape it in one of two ways:

1) using the @ prefix which escapes all backslashes, or
2) by escaping the backslash using another one, e.g. "\\W+"

I personally prefer and recommend the @ prefix because I don't have to doit
for further slashes.
--
Stanimir Stoyanovhttp://stoyanoff.info

"puzzlecrac ker" <ironsel2...@gm ail.comwrote in message

news:9d******** *************** ***********@o40 g2000prn.google groups.com...
I understand that the following would split the line in words space
separated: string[] words = Regex.Split(tex t, @"\W+"); Why do we need
@ before regular expression?
Thanks
I see, I use @ to escape line-breaks, that seems another useful
application.

Thanks
Nov 3 '08 #3
One thing to note though, if you use the @ prefix line breaks will not work.
This is, essentially, because the line break is escaped and the string is
interpreted as 'slash, r, slash, n' and not 'carriage return, line break'.
--
Stanimir Stoyanov
http://stoyanoff.info

"puzzlecrac ker" <ir*********@gm ail.comwrote in message
news:8b******** *************** ***********@s9g 2000prg.googleg roups.com...
On Nov 3, 9:09 am, "Stanimir Stoyanov" <stoya...@REMOV ETHIS.live.com>
wrote:
In C# the backslash (\) serves for escaping characters, and when you want
to
include the literal backslash you have to escape it in one of two ways:

1) using the @ prefix which escapes all backslashes, or
2) by escaping the backslash using another one, e.g. "\\W+"

I personally prefer and recommend the @ prefix because I don't have to do
it
for further slashes.
--
Stanimir Stoyanovhttp://stoyanoff.info

"puzzlecrac ker" <ironsel2...@gm ail.comwrote in message

news:9d******** *************** ***********@o40 g2000prn.google groups.com...
I understand that the following would split the line in words space
separated: string[] words = Regex.Split(tex t, @"\W+"); Why do we need
@ before regular expression?
Thanks
I see, I use @ to escape line-breaks, that seems another useful
application.

Thanks

Nov 3 '08 #4
Stanimir Stoyanov wrote:
One thing to note though, if you use the @ prefix line breaks will
not work. This is, essentially, because the line break is escaped and
the string is interpreted as 'slash, r, slash, n' and not 'carriage
return, line break'.
Line breaks work fine.

But they look like this:

string s = @"
";

not this:

string s = @"\r\n";
>
"puzzlecrac ker" <ir*********@gm ail.comwrote in message
news:8b******** *************** ***********@s9g 2000prg.googleg roups.com...
On Nov 3, 9:09 am, "Stanimir Stoyanov" <stoya...@REMOV ETHIS.live.com>
wrote:
>In C# the backslash (\) serves for escaping characters, and when you
want to
include the literal backslash you have to escape it in one of two
ways: 1) using the @ prefix which escapes all backslashes, or
2) by escaping the backslash using another one, e.g. "\\W+"

I personally prefer and recommend the @ prefix because I don't have
to do it
for further slashes.
--
Stanimir Stoyanovhttp://stoyanoff.info

"puzzlecracker " <ironsel2...@gm ail.comwrote in message

news:9d******* *************** ************@o4 0g2000prn.googl egroups.com...
>>I understand that the following would split the line in words space
separated: string[] words = Regex.Split(tex t, @"\W+"); Why do we
need @ before regular expression?
>>Thanks

I see, I use @ to escape line-breaks, that seems another useful
application.

Thanks

Nov 3 '08 #5
Thanks for pointing this out, Ben.

"Ben Voigt [C++ MVP]" <rb*@nospam.nos pamwrote in message
news:et******** ******@TK2MSFTN GP04.phx.gbl...
Stanimir Stoyanov wrote:
>One thing to note though, if you use the @ prefix line breaks will
not work. This is, essentially, because the line break is escaped and
the string is interpreted as 'slash, r, slash, n' and not 'carriage
return, line break'.

Line breaks work fine.

But they look like this:

string s = @"
";

not this:

string s = @"\r\n";
>>
"puzzlecracker " <ir*********@gm ail.comwrote in message
news:8b******* *************** ************@s9 g2000prg.google groups.com...
On Nov 3, 9:09 am, "Stanimir Stoyanov" <stoya...@REMOV ETHIS.live.com>
wrote:
>>In C# the backslash (\) serves for escaping characters, and when you
want to
include the literal backslash you have to escape it in one of two
ways: 1) using the @ prefix which escapes all backslashes, or
2) by escaping the backslash using another one, e.g. "\\W+"

I personally prefer and recommend the @ prefix because I don't have
to do it
for further slashes.
--
Stanimir Stoyanovhttp://stoyanoff.info

"puzzlecracke r" <ironsel2...@gm ail.comwrote in message

news:9d****** *************** *************@o 40g2000prn.goog legroups.com...

I understand that the following would split the line in words space
separated: string[] words = Regex.Split(tex t, @"\W+"); Why do we
need @ before regular expression?

Thanks

I see, I use @ to escape line-breaks, that seems another useful
application.

Thanks

Nov 3 '08 #6

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

3
20978
by: Martin Lucas-Smith | last post by:
Is there some way of using ereg to detect when certain filename extensions are supplied and to return false if so, WITHOUT using the ! operator before ereg () ? I have an API that allows as an input a regular expression, enabling the administrator to ensure a file upload matches a certain pattern. For instance, supplying the string ...
5
2339
by: Lukas Holcik | last post by:
Hi everyone! How can I simply search text for regexps (lets say <a href="(.*?)">(.*?)</a>) and save all URLs(1) and link contents(2) in a dictionary { name : URL}? In a single pass if it could. Or how can I replace the html &entities; in a string "blablabla&amp;blablabal&amp;balbalbal" with the chars they mean using re.sub? I found out they are...
1
1507
by: joh12005 | last post by:
Hello, here is a trouble that i had, i would like to resolve it with python, even if i still have no clue on how to do it. i had many small "text" files, so to speed up processes on them, i used to copy them inside a huge one adding some king of xml separator : <file name="...">
5
4147
by: Illya Havsiyevych | last post by:
Hello Anybody knows regexp used in CodeModule Find Method I'm trying to use regexp's to find all procedures in CodeModule Maybe there is other way in Access Thank You Illya
4
7458
by: Jon Maz | last post by:
Hi All, I want to strip the accents off characters in a string so that, for example, the (Spanish) word "práctico" comes out as "practico" - but ignoring case, so that "PRÁCTICO" comes out as "PRACTICO". What's the best way to do this? TIA,
6
1828
by: Edward | last post by:
I need to validate a text box entry, but ONLY if it is 17 characters, otherwise I have to ignore it. My regular expression for the validation is: ^(({9})()()(\d{6}))$ Can I adapt this to "fire" only if the string in question is 17 chars in length? Or do I have to do this server-side? Thanks
11
2913
by: HopfZ | last post by:
I coudn't understand some behavior of RegExp.test function. Example html code: ---------------- <html><head></head><body><script type="text/javascript"> var r = /^https?:\/\//g; document.write( ); </script></body></html> ---------------------
4
1196
by: eight02645999 | last post by:
hi suppose i have a string like test1?test2t-test3*test4*test5$test6#test7*test8 how can i construct the regexp to get test3*test4*test5 and test7*test8, ie, i want to match * and the words before and after? thanks
3
1981
by: VUNETdotUS | last post by:
Hi, I am working with this regexp to extract address: city, state, and zip. This version kinda works but it extracts one element of an array instead of three and keeps my "city" too long, including all text before it. ..................... var regex = /\s*(.*)\s*,\s*({2})\s+(\d{5}(\-\d{4})?)\s*/g; function doit(){ var arr =...
12
2046
by: EME | last post by:
typeof new RegExp ---------------------------------------------------- Why (new RegExp) type is function not object very thanks for you consulation
0
7695
marktang
by: marktang | last post by:
ONU (Optical Network Unit) is one of the key components for providing high-speed Internet services. Its primary function is to act as an endpoint device located at the user's premises. However, people are often confused as to whether an ONU can Work As a Router. In this blog post, we’ll explore What is ONU, What Is Router, ONU & Router’s main...
0
7922
Oralloy
by: Oralloy | last post by:
Hello folks, I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>". The problem is that using the GNU compilers, it seems that the internal comparison operator "<=>" tries to promote arguments from unsigned to signed. This is as boiled down as I can make it. ...
0
8119
jinu1996
by: jinu1996 | last post by:
In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven tapestry of website design and digital marketing. It's not merely about having a website; it's about crafting an immersive digital experience that...
0
7964
tracyyun
by: tracyyun | last post by:
Dear forum friends, With the development of smart home technology, a variety of wireless communication protocols have appeared on the market, such as Zigbee, Z-Wave, Wi-Fi, Bluetooth, etc. Each protocol has its own unique characteristics and advantages, but as a user who is planning to build a smart home system, I am a bit confused by the...
1
5509
isladogs
by: isladogs | last post by:
The next Access Europe User Group meeting will be on Wednesday 1 May 2024 starting at 18:00 UK time (6PM UTC+1) and finishing by 19:30 (7.30PM). In this session, we are pleased to welcome a new presenter, Adolph Dupré who will be discussing some powerful techniques for using class modules. He will explain when you may want to use classes...
0
3653
by: TSSRALBI | last post by:
Hello I'm a network technician in training and I need your help. I am currently learning how to create and manage the different types of VPNs and I have a question about LAN-to-LAN VPNs. The last exercise I practiced was to create a LAN-to-LAN VPN between two Pfsense firewalls, by using IPSEC protocols. I succeeded, with both firewalls in...
0
3637
by: adsilva | last post by:
A Windows Forms form does not have the event Unload, like VB6. What one acts like?
1
2111
by: 6302768590 | last post by:
Hai team i want code for transfer the data from one system to another through IP address by using C# our system has to for every 5mins then we have to update the data what the data is updated we have to send another system
0
936
bsmnconsultancy
by: bsmnconsultancy | last post by:
In today's digital era, a well-designed website is crucial for businesses looking to succeed. Whether you're a small business owner or a large corporation in Toronto, having a strong online presence can significantly impact your brand's success. BSMN Consultancy, a leader in Website Development in Toronto offers valuable insights into creating...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.