perl script to replace the xml values - perl

Question

I have this XML file:
<?xml version="1.0" encoding="ISO-8859-1"?>
<BroadsoftDocument protocol = "OCI" xmlns="C" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<sessionId xmlns="">169.254.52.85,16602326,1324821125562</sessionId>
<command xsi:type="UserAddRequest14sp9" xmlns="">
<serviceProviderId>AtyafBahrain</serviceProviderId>
<groupId>LoadTest</groupId>
<userId>user_0002#atyaf.me</userId>
<lastName>0002</lastName>
<firstName>user</firstName>
<callingLineIdLastName>0002</callingLineIdLastName>
<callingLineIdFirstName>user</callingLineIdFirstName>
<password>123456</password>
<language>English</language>
<timeZone>Asia/Bahrain</timeZone>
<address/>
</command>
</BroadsoftDocument>
and I need to replace the values of some fields (UserID, firstName, password) and output the file to be saved with the same name.
Using the code below I will change the syntax of the xml fields (xml format gets disturbed):
XMLout( $xml, KeepRoot => 1, NoAttr => 1, OutputFile => $xml_file, );
can you please advice how to edit the xml file without changing its syntax?

Answer 1

You can checkout XML::Simple parser for perl. You can refer to the CPAN site. I have used it for parsing XML files but I think this should allow modification as well.

Answer 2

# open XML file (input the XML file name)
open (INPUTFILE, "+<$filename_1");
#file = <INPUTFILE>;
seek INPUTFILE,0,0;
foreach $file (#file)
{
# Find string_1 and replace it by string_2
$file =~ s/$str_1/$str_2/g;
# write to file
print INPUTFILE $file;
}
close INPUTFILE;