Help with Regex C#

Question

I am trying to find some patterns. they can be:

1. "fourty|40;TOFIND|1234;fifty|50"
2. "TOFIND|1234;fifty|50"
3. "fourty|40;TOFIND|1234"

as you can see, the TOFIND|1234 can appear inside the statement (before ; and after ;), or it can have only before ; or it can have none.

It should NOT include examples:

MTOFIND|1234;
;TOFIND|1234Q

How can I find it?

I tried: Regex re = new Regex("TOFIND|1234" + "[;?]");

But I am not sure its correct.

Please help!

Thanks

You should propose what some negative samples could be, e.g., what if there was XTOFIND|1234, or TOFIND|12345. — tofutim
– tofutim, Commented May 24, 2011 at 15:37
would you like to extract the TOFIND from the line? Or do you want to get only those lines that have TOFIND in it? — yas4891
– yas4891, Commented May 24, 2011 at 15:37
I need it to support only beginning is empty, end is empty or ; before or ; at the end — Himberjack
– Himberjack, Commented May 25, 2011 at 6:51

Erick Petrucelli · Accepted Answer · 2011-05-24 15:31:23Z

1

What about any character before or after the exact string TOFIND|1234?

Regex re = new Regex(".*(TOFIND\|1234).*");

answered May 24, 2011 at 15:31

Erick Petrucelli

15.1k9 gold badges68 silver badges89 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Himberjack Over a year ago

Not allowed. Only ^ or $ (respectively) or only ; that can appear at the beginning or end

ShaneBlake · Accepted Answer · 2011-05-24 15:35:49Z

0

Regex re = new Regex("(?:[^;])TOFIND\|1234(?=[;$])");

answered May 24, 2011 at 15:35

ShaneBlake

11.1k2 gold badges28 silver badges43 bronze badges

Comments

Yuri · Accepted Answer · 2011-05-24 15:36:05Z

0

You my try this: ";?TOFIND|1234;?" This will include ";"s in the match.

answered May 24, 2011 at 15:36

Yuri

813 bronze badges

Comments

Hogan · Accepted Answer · 2011-05-24 15:37:04Z

0

I would do it like this

string FindIt(string inStr)
{
    for each (string item in inStr.Split(new char [] {';'}))
    {
       string [] eles = item.Split(new char [] {'|'});
         if (eles[0] == "TOFIND")
           return eles[1];
    }
    return "";
}

answered May 24, 2011 at 15:37

Hogan

70.7k10 gold badges83 silver badges119 bronze badges

Comments

yas4891 · Accepted Answer · 2011-05-24 16:12:36Z

0

To get the lines that contain TOFIND

@"TOFIND\|.*|.*;TOFIND.*"

I found this tool over here to be of great help: Rad Software Regular Expression Designer

edited May 24, 2011 at 16:12

answered May 24, 2011 at 15:43

yas4891

4,8723 gold badges37 silver badges56 bronze badges

Comments

Erick Petrucelli · Accepted Answer · 2011-05-25 13:05:19Z

0

Based on your comments and edits, here we go... This is the Regex that you could use:

Regex r = new Regex(@";?[^\w](TOFIND\|1234)[^\w];?");

So, using the folowing samples:

1. "fourty|40;TOFIND|1234;fifty|50"
2. "TOFIND|1234;fifty|50"
3. "fourty|40;TOFIND|1234"
4. "MTOFIND|1234;"
5. ";TOFIND|1234Q"
6. "some|15;TOFIND|1234;"
7. ";TOFIND|1234;blabla|100"

It will match the lines 1, 2, 3, 6 and 7.

Let's explain the rules:

";?"  // We need 0 or 1 semi-colon before.
"[^\w]"  // We can't have any char (a-zA-Z0-9) before.
"(TOFIND\|1234)"  // We must have exactly TOFIND|1234.
"[^\w]"  // We can't have any char after.
";?"  // We need 0 or 1 semi-colon after.

If I understood well all your needs, thats it.

answered May 25, 2011 at 13:05

Erick Petrucelli

15.1k9 gold badges68 silver badges89 bronze badges

Collectives™ on Stack Overflow

Help with Regex C#

6 Answers 6

1 Comment

Comments

Comments

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

6 Answers 6

1 Comment

Comments

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related