One can also do it without any XML parser. Here's an example 

my $str = <<EOF;
<students>
    <student>
        <name>John</name>
        <id>001</id>
        <gpa>A</gpa>
    </student>
    <student>
        <name>John</name>
        <id>002</id>
        <gpa>C</gpa>
    </student>
</students>
EOF

$str =~ s/<student>(.*?)<\/student>/check_record($1)/gse;

print $str;

sub check_record
{
    my $rec = shift;
    $rec =~ s/(<gpa>\s*)C(\s*<\/gpa>)/$1B$2/ if($rec =~ /<id>\s*002\s*
+<\/id>/);
    return "<student>$rec</student>";
}

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In reply to Re: How can I replace a line (tag) in an XML file? by andal
in thread How can I replace a line (tag) in an XML file? by perlPractioner

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