Regex should Replace the Contents in xml file, but not the tag name

Question

Please see the code below:

Match match = Regex.Match(doc.OuterXml, "\\b" + l_sOldvalue + "\\b");
if ((match.Success) && (l_bflag))
{
    string pattern = "\\b" + l_sOldvalue + "\\b";
    string l_sChangexml = Regex.Replace(doc.OuterXml, pattern, l_sNewValue);
    doc.LoadXml(l_sChangexml);
}

Here I'm using RegEx Match and Replace, but it replaces the tag names also. For me the tag name should not be replaced.

doc.outerxml --> contains complete xml file

Can any one please solve this?

Please check the best answer to [this question](http://stackoverflow.com/questions/1732348/regex-match-open-tags-except-xhtml-self-contained-tags?rq=1). — John Willemse, Mar 13 '14 at 08:31
I checked but , it is not clear , can you please share the exact regex to me — Sakthi Raj, Mar 13 '14 at 08:43
They're pointing out that using Regex is the **wrong** tool for the job. There's an entire [Namespace](http://msdn.microsoft.com/en-us/library/system.xml(v=vs.110).aspx) dedicated to XML processing in .NET framework. — Damien_The_Unbeliever, Mar 13 '14 at 09:11
I want a solution in regex only , It will be easier for me to process — Sakthi Raj, Mar 13 '14 at 11:46

score 1 · Answer 1 · answered Mar 13 '14 at 13:15

1

You want to use a "negative lookbehind" in your Regex. E.g. if you want to make sure that you don't catch a tag like <blafasel> or </blafasel>, but all occurences of blafasel as a single word, use the following pattern:

var pattern = @"(?i)(?<![</])\bblafasel\b";

Or to use your sample:

string pattern = @"(?i)(?<![</])\b" + l_sOldvalue + @"\b";    
Match match = Regex.Match(doc.OuterXml, pattern);

if ((match.Success) && (l_bflag))
{
    string l_sChangexml = Regex.Replace(doc.OuterXml, pattern, l_sNewValue);
    doc.LoadXml(l_sChangexml);
}

Please show a sample of your XML the next time, that would make it easier.

HTH

answered Mar 13 '14 at 13:15

Alexander Müller

98
1
6

Thank you very much , now it is worked for me , once again big thanks :) – Sakthi Raj Mar 13 '14 at 13:46
Can you please explain the regular expression used below @"(?i)(?<![])\bblafasel\b"; – Sakthi Raj Mar 13 '14 at 13:48
It says `(?i)` regexengine, watch out: `(?<!` I don't want to see left from my searchstring the following `[]` characters `\bblafasel\b` and my searchstring is the complete word blafasel. – Alexander Müller Mar 13 '14 at 13:59
Thank you , i would like to learn more examples in regular expression , can you please share me any links to learn more – Sakthi Raj Mar 13 '14 at 14:30
The resource that helped me most was the book [Introducing Regular Expressions](http://shop.oreilly.com/product/0636920012337.do). Its approach is very good and the samples are quick to understand. – Alexander Müller Mar 13 '14 at 14:42
Thank you , I think we have to but the book , do you have any free dwonloads link ? :) – Sakthi Raj Mar 13 '14 at 15:29
Hello , The above example is fine , but can you please update the regex and share me , in which the attribute name also should not be renamed eg : here "id" should not be renamed can you please us the solution asap – Sakthi Raj Mar 17 '14 at 06:46
@Muller :- can you please help me for the above mentioned comments – Sakthi Raj Mar 17 '14 at 12:30

vlad_tepesch · Answer 2 · 2014-03-13T14:59:20.807

0

hmm - removing all content could be done by removing everything between > and < or did i miss something? additional to this all tag-attributes have to be removed that can be done by deleting everything between <charactersToNextWhitespace and >.

may be (not testet it)

s/>.*?</></g
s/(<\w+)\W.*?>/\1/g;

edited Mar 13 '14 at 14:59

answered Mar 13 '14 at 14:19

vlad_tepesch

6,681
1
38
80

I used this regex , It is perfectly working @"(?i) @"(?i)(?<![])\b" + l_sOldvalue + @"\b"; – Sakthi Raj Mar 13 '14 at 14:40
Hello , The above example is fine , but can you please update the regex and share me , in which the attribute name also should not be renamed eg : here "id" should not be renamed can you please us the solution asap – Sakthi Raj Mar 17 '14 at 11:57
@SakthiRaj i do not completely understand what you want. do you only want the attribute names (eg: ``) or just or do you want jast to keep the id-attrib inclusive its valu (eg: ``)? the last one is easy, if the id attribute is always the first attribute. – vlad_tepesch Mar 17 '14 at 12:13
Hello, I don't want to change the attribute name eg-"id" , but attribute value can be changed eg-"10", I think we have to modify the following @"(?i)(?<![])\b" + l_sOldvalue + @"\b" – Sakthi Raj Mar 17 '14 at 12:29

Regex should Replace the Contents in xml file, but not the tag name

2 Answers2