Text File Manipulation

Questions
1

Hey,
I am searching for a possibility to search keywords in a text file and replace the text between this keywords.
Basically textfile:

... some text...
tag1originaltexttag2
...sometext

The idea is to search for tag1 and tag2 and substitute the text delimited by these.
E.g:
with applying a function like function[textfile,“tag1”,“tag2”,“newtext”]

... some text...
tag1newtexttag2
...sometext

I have tried several combinations of input output stream manipulations, Find, Position, etc.,
but didn’t find an appropriate solution.
Is there an easy function to accomplish this?
Thanks in advance

2

Can you adapt something like this?

fun[textfile_, tag1_, tag2_, newtext_] := (
   old = Import[textfile]; 
   new = StringReplace[old, RegularExpression[tag1<>".*"<>tag2]->tag1<>newtext<>tag2];
   Export[textfile, new]
   );
fun["textfile.txt", "tag1", "tag2", "newtext"];

You may need to insert the path to your textfile if it isn’t in a place that Mathematica knows to look.

3

A less elegant way. Click the pull down menu “Edit” select “Find” then type in the text you want to change.