How can I replace a certain part in a xml file with a definied string?
<tag1></tag2>
<tag2></tag2>
...etc
<soundcard num=0>
<name>test123</name>
</soundcard>
<soundcard num=1>
<name>test123</name>
</soundcard>
<soundcard num=2>
<name>test123</name>
</soundcard>
<tag5></tag5>
replace all soundcard parts that the result looks like that:
<tag1></tag2>
<tag2></tag2>
...etc
{0}
<tag5></tag5>
I'm using c# .net 3.5 and I thougt of a regex solution
If it has to be a regex, your XML file is well-formed, and you know (say, from the DTD) that <soundcard> tags can't be nested, then you can use
(<soundcard.*?</soundcard>\s*)+
and replace all with {0}.
In C#:
resultString = Regex.Replace(subjectString, @"(<soundcard.*?</soundcard>\s*)+", "{0}", RegexOptions.Singleline);
For a quick-and-dirty fix to a one-off problem, I think that's OK. It's not OK to think of regex as the proper tool to handle XML in general.
Personally I would use Linq to XML and remove the entities and replace it with a Text Node.
Update Apr 16/2010 4:40PM MST
Here's an example of Linq to XML, I'm a bit rusty but it should at least give you an idea of how this is done.
XElement root = XElement.Load("myxml.xml");
var soundcards = select el from root.Elements() where el.Name == "soundcard" select el;
var prev_node = soundcards.First().PreviousNode;
// Remove Nodes
foreach(XElement card in soundcards)
card.Remove();
// Build your content here into a variable called newChild
prev_node.AddAfterSelf(newChild);
My suggestion would be to use an XSLT transformation to replace the tags you want to replace with a known tag, say , and then String.Replace('', '{0}');.
I echo what Johannes said, do NOT try to build REs to do this. As your XML gets more complex, you error rate will increase.
