Here is an SSCCE:

use strict;
use warnings;

use XML::LibXML;
use Test::More tests => 1;

my $in = '<seg><foo mid="0" mtype="seg"><g id="1">Need to export this 
+text</g></foo></seg>';
my $want = '<g id="1">Need to export this text</g>';
my $xml = XML::LibXML->load_xml (string => $in);

my $have = $xml->getElementsByTagName ('g')->shift->toString;
is ($have, $want);
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Hi,

Thank you for your help. I gave it a try and it works when it has tags. However, there are cases where the extracted text doesn't contain tags (i.e. <seg><foo mid="0" mtype="seg">Need to export this text</foo></seg>.

i used this one my $mrktext = $mrk->getElementsByTagName ('*')->shift->toString;

.

What is your full code? What output do you get? What do you expect?

Unless you tell us that, we can't figure out where you're going wrong.

Here's the code for an example I created:

use strict;

my $str = q{<seg><foo mid="0" mtype="seg"><g id="1">Need to export thi
+s text</g></foo></seg>};
my $xml = XML::LibXML->load_xml(string => $str);

print $xml->getElementsByTagName("g")->shift->toString, "\n";
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The output is:

<g id="1">Need to export this text</g>
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Which is exactly what I'd expect it to be.

What is your full code? What output do you get? What do you expect?

toby döt ink

As a side note you keep posting things in the wrong section of the forum. Please read and understand Where should I post X?, which is displayed each time you post.

Problem #1: You ask for the foo nodes that are children of the document. There are no such nodes.

$doc->findnodes('foo')
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$doc->findnodes('seg/foo')
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$doc->findnodes('/seg/foo')
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Problem #2: You ask for the text children of the foo element, but it doesn't have any. It's not even text you want!

$foo->findnodes('text()')
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join('', map { $_->toString() } $foo_node->childNodes)
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join('', $foo_node->childNodes)
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Also,

$foo->findvalue('@mid')
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is better written as

$foo->getAttribute('mid')
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So, we get

use strict;
use warnings qw( all );
use feature qw( say );

use XML::LibXML qw( );

my $xml = <<'__EOS__';
<seg><foo mid="0" mtype="seg"><g id="1">Need to export this text</g></
+foo></seg>
__EOS__

my $doc = XML::LibXML->new->parse_string($xml);
for my $foo_node ($doc->findnodes('/seg/foo')) {
   my $mid = $foo_node->getAttribute('mid');
   my $inner_xml = join('', $foo_node->childNodes);
   say "$mid $inner_xml";
}
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use XML::LibXML;

my $xml = q|
<seg>
    <foo mid="0" mtype="seg">
        <g id="1">Need to export this text</g>
    </foo>
    <foo mid="1" mtype="seg">
        Need to export this text also
    </foo>
</seg>|;

my $doc = XML::LibXML->load_xml(string => $xml);
my @foos = $doc->findnodes('//foo');

for my $foo (@foos) {
    my $mid = $foo->getAttribute('mid');
    print "mid: $mid ";
    my @childnodes = $foo->childNodes();
    if (@childnodes) {
        for my $node (@childnodes) {
            print $node->toString, "\n";
        }
    }
    else {
        print $foo->textContent, "\n";
    }
}
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mid: 0 
<g id="1">Need to export this text</g>

mid: 1 
Need to export this text also
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