Hi,

I am using XML::LibXML module to parse an XML file and read attributes and node values using XPaths. I am able to read the value of nodes all right; but I am having trouble reading the values of attributes - I am not able to get the right approach (XPath and API to read attributes). Please help.

The sample XML file that I am trying to read: 
<root>
    <head>
        <node1 attr1="Node1 Attribute">
                Node1 Value
        </node1>
    </head>
</root>

[download]

The PERL script that I am using to read attributes' values : 
use XML::LibXML;


    $inp             = $ARGV[0];

    # create object
    my $parser = XML::LibXML->new();


    # read input XML file
    my $inp_tree = $parser->parse_file($inp);
    my $inp_root = $inp_tree->getDocumentElement;
    
    my $root_text = $inp_root->toString();
    
    $rule_source = "node1//@attr1";
    
    my @inp_search_nodes = $inp_root->findnodes($rule_source);
                    
    my $inp_search_results = scalar @inp_search_nodes;
                                                                    
    if ( 0 == $inp_search_results )
    {
        print "XPath $rule_source not found! \n";
                    
    }
    else
    {
        my $path_text = $inp_search_nodes[ 0 ]->findvalue(".");
            print "Xpath ->:  $path_text\n";

        my $val = $inp_search_nodes[ 0 ]->textContent();              
+                            
            print "Value of XPath $rule_source : $val \n";
    }

[download]


I am trying to read the value of the attrbbute "attr1" of the node "node1".


When I use XPath "/head/node1/@attr1", I get this result when I try toi run the PERL scri[t shown above: 
XPath error : Invalid expression
/head/node1/
            ^

[download]


When I use this XPath - "head/node1/@attr1", I get the same error listed above

When I use this XPath - "head/node1@attr1", the code prints the value of the node node1 and NOT the value of the attribute.

When I use this XPath - "/head/node1@attr1", I get this error: "XPath /head/node1 not found"


So, which Xpath should I use to read the value of the attribute of a node?




In reply to XPath to read attributes using XML::LibXML ... by biswanath_c

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