Saludos,
Necesito leer los datos de un xml de factura electronica e intentado con los ejemplos q he encontrado pero no he logrado en su totalidad
este es el archivo xml
<?xml version="1.0" encoding="UTF-8"?>
<Invoice xmlns="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2" xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2" xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2" xmlns:ds="http://www.w3.org/2000/09/xmldsig#" xmlns:ext="urn:oasis:names:specification:ubl:schema:xsd:CommonExtensionComponents-2">
<ext:UBLExtensions>
<ext:UBLExtension>
<ext:ExtensionContent><ds:Signature Id="SignatureSP"><ds:SignedInfo><ds:CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315"/><ds:SignatureMethod Algorithm="http://www.w3.org/2000/09/xmldsig#rsa-sha1"/><ds:Reference URI=""><ds:Transforms><ds:Transform Algorithm="http://www.w3.org/2000/09/xmldsig#enveloped-signature"/></ds:Transforms><ds:DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1"/><ds:DigestValue>xh/m/3wVPDnhU5JOYAoSnWTOMe0=</ds:DigestValue></ds:Reference></ds:SignedInfo><ds:SignatureValue>MPY7AcpWsLeQzz59sYwEODkqJA+NQmPAnUMpdi5O1FZMq2wFDF0cv+2bdHqwJtqv1Rb7KiyOocoM7RpKQqH2JdMN1zNfxYx/z4vkw2Ta5Hj78EV5F9eVJhgCFhho2z4w0GmjO1opnUk6W6Uj30yh5OXfKdHsqiojk1F66dCQHXS/iWjnzsTcPx615ltoTItzPnQ7AaENuumc6il+SHro9ju2Izdf780DVXf1QwKOAtaVJwdmpBd1P1WjMBKdgHEdl6pI0pO6p7D+jujz+DC03UlkznGL8z/UCWAvF3yVNJ/vAjE9JLQV0ZPGHGD1i34PlaO/WCPS42n5KpZWMiArAg==</ds:SignatureValue><ds:KeyInfo><ds:X509Data><ds:X509Certificate>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</ds:X509Certificate></ds:X509Data></ds:KeyInfo></ds:Signature></ext:ExtensionContent>
</ext:UBLExtension>
</ext:UBLExtensions>
<cbc:UBLVersionID>2.1</cbc:UBLVersionID>
<cbc:CustomizationID>2.0</cbc:CustomizationID>
<cbc:ID>F001-30</cbc:ID>
<cbc:IssueDate>2021-02-18</cbc:IssueDate>
<cbc:IssueTime>00:00:00</cbc:IssueTime>
<cbc:DueDate>2021-02-18</cbc:DueDate>
<cbc:InvoiceTypeCode listID="0101">01</cbc:InvoiceTypeCode>
<cbc:Note languageLocaleID="1000"><![CDATA[TRESCIENTOS OCHENTA CON 20/100 SOLES]]></cbc:Note>
<cbc:DocumentCurrencyCode>PEN</cbc:DocumentCurrencyCode>
<cac:Signature>
<cbc:ID>20606177896</cbc:ID>
<cbc:Note><![CDATA[LAFARYAT II E.I.R.L.]]></cbc:Note>
<cac:SignatoryParty>
<cac:PartyIdentification>
<cbc:ID>20606177896</cbc:ID>
</cac:PartyIdentification>
<cac:PartyName>
<cbc:Name><![CDATA[LAFARYAT II E.I.R.L.]]></cbc:Name>
</cac:PartyName>
</cac:SignatoryParty>
<cac:DigitalSignatureAttachment>
<cac:ExternalReference>
<cbc:URI>#SIGN-EMPRESA</cbc:URI>
</cac:ExternalReference>
</cac:DigitalSignatureAttachment>
</cac:Signature>
<cac:AccountingSupplierParty>
<cac:Party>
<cac:PartyIdentification>
<cbc:ID schemeID="6">20606177896</cbc:ID>
</cac:PartyIdentification>
<cac:PartyName>
<cbc:Name><![CDATA[LAFARYAT II E.I.R.L.]]></cbc:Name>
</cac:PartyName>
<cac:PartyLegalEntity>
<cbc:RegistrationName><![CDATA[LAFARYAT II E.I.R.L.]]></cbc:RegistrationName>
<cac:RegistrationAddress>
<cbc:ID>110201</cbc:ID>
<cbc:AddressTypeCode>0000</cbc:AddressTypeCode>
<cbc:CitySubdivisionName>NONE</cbc:CitySubdivisionName>
<cbc:CityName>CHINCHA</cbc:CityName>
<cbc:CountrySubentity>ICA</cbc:CountrySubentity>
<cbc:District>CHINCHA ALTA</cbc:District>
<cac:AddressLine>
<cbc:Line><![CDATA[AV. ALVA MAURTUA NRO. 598 OTR. AVENIDA ICA - CHINCHA - CHINCHA ALTA]]></cbc:Line>
</cac:AddressLine>
<cac:Country>
<cbc:IdentificationCode>PE</cbc:IdentificationCode>
</cac:Country>
</cac:RegistrationAddress>
</cac:PartyLegalEntity>
</cac:Party>
</cac:AccountingSupplierParty>
<cac:AccountingCustomerParty>
<cac:Party>
<cac:PartyIdentification>
<cbc:ID schemeID="6">20451640047</cbc:ID>
</cac:PartyIdentification>
<cac:PartyLegalEntity>
<cbc:RegistrationName><![CDATA[MEDICOS & FISIOTERAPEUTAS FISIOAPAIN E.I.R.L]]></cbc:RegistrationName>
<cac:RegistrationAddress>
<cac:AddressLine>
<cbc:Line><![CDATA[CAL.DANIEL OLAECHEA NRO. 260 DPTO. 504 URB. HUASCAR (CRUCE CON AV. INCA RIPAC)]]></cbc:Line>
</cac:AddressLine>
<cac:Country>
<cbc:IdentificationCode>PE</cbc:IdentificationCode>
</cac:Country>
</cac:RegistrationAddress>
</cac:PartyLegalEntity>
</cac:Party>
</cac:AccountingCustomerParty>
<cac:TaxTotal>
<cbc:TaxAmount currencyID="PEN">58</cbc:TaxAmount>
<cac:TaxSubtotal>
<cbc:TaxableAmount currencyID="PEN">322.2</cbc:TaxableAmount>
<cbc:TaxAmount currencyID="PEN">58</cbc:TaxAmount>
<cac:TaxCategory>
<cac:TaxScheme>
<cbc:ID>1000</cbc:ID>
<cbc:Name>IGV</cbc:Name>
<cbc:TaxTypeCode>VAT</cbc:TaxTypeCode>
</cac:TaxScheme>
</cac:TaxCategory>
</cac:TaxSubtotal></cac:TaxTotal>
<cac:LegalMonetaryTotal>
<cbc:LineExtensionAmount currencyID="PEN">322.2</cbc:LineExtensionAmount>
<cbc:TaxInclusiveAmount currencyID="PEN">380.2</cbc:TaxInclusiveAmount>
<cbc:PayableAmount currencyID="PEN">380.2</cbc:PayableAmount>
</cac:LegalMonetaryTotal><cac:InvoiceLine>
<cbc:ID>1</cbc:ID>
<cbc:InvoicedQuantity unitCode="NIU">5.00</cbc:InvoicedQuantity>
<cbc:LineExtensionAmount currencyID="PEN">80.51</cbc:LineExtensionAmount>
<cac:PricingReference>
<cac:AlternativeConditionPrice>
<cbc:PriceAmount currencyID="PEN">19.00000</cbc:PriceAmount>
<cbc:PriceTypeCode>01</cbc:PriceTypeCode>
</cac:AlternativeConditionPrice>
</cac:PricingReference>
<cac:TaxTotal>
<cbc:TaxAmount currencyID="PEN">14.49</cbc:TaxAmount>
<cac:TaxSubtotal>
<cbc:TaxableAmount currencyID="PEN">80.51</cbc:TaxableAmount>
<cbc:TaxAmount currencyID="PEN">14.49</cbc:TaxAmount>
<cac:TaxCategory>
<cbc:Percent>18.00</cbc:Percent>
<cbc:TaxExemptionReasonCode>10</cbc:TaxExemptionReasonCode>
<cac:TaxScheme>
<cbc:ID>1000</cbc:ID>
<cbc:Name>IGV</cbc:Name>
<cbc:TaxTypeCode>VAT</cbc:TaxTypeCode>
</cac:TaxScheme>
</cac:TaxCategory>
</cac:TaxSubtotal>
</cac:TaxTotal>
<cac:Item>
<cbc:Description><![CDATA[FLORA BALANCE 2000 MILLONES/5ML SUSP. ORAL CJA X 10 FCOS]]></cbc:Description>
<cac:SellersItemIdentification>
<cbc:ID>00076</cbc:ID>
</cac:SellersItemIdentification>
</cac:Item>
<cac:Price>
<cbc:PriceAmount currencyID="PEN">16.10000</cbc:PriceAmount>
</cac:Price>
</cac:InvoiceLine><cac:InvoiceLine>
<cbc:ID>2</cbc:ID>
<cbc:InvoicedQuantity unitCode="NIU">2.00</cbc:InvoicedQuantity>
<cbc:LineExtensionAmount currencyID="PEN">21.36</cbc:LineExtensionAmount>
<cac:PricingReference>
<cac:AlternativeConditionPrice>
<cbc:PriceAmount currencyID="PEN">12.60000</cbc:PriceAmount>
<cbc:PriceTypeCode>01</cbc:PriceTypeCode>
</cac:AlternativeConditionPrice>
</cac:PricingReference>
<cac:TaxTotal>
<cbc:TaxAmount currencyID="PEN">3.84</cbc:TaxAmount>
<cac:TaxSubtotal>
<cbc:TaxableAmount currencyID="PEN">21.36</cbc:TaxableAmount>
<cbc:TaxAmount currencyID="PEN">3.84</cbc:TaxAmount>
<cac:TaxCategory>
<cbc:Percent>18.00</cbc:Percent>
<cbc:TaxExemptionReasonCode>10</cbc:TaxExemptionReasonCode>
<cac:TaxScheme>
<cbc:ID>1000</cbc:ID>
<cbc:Name>IGV</cbc:Name>
<cbc:TaxTypeCode>VAT</cbc:TaxTypeCode>
</cac:TaxScheme>
</cac:TaxCategory>
</cac:TaxSubtotal>
</cac:TaxTotal>
<cac:Item>
<cbc:Description><![CDATA[LEVOGLOB 500MG CAJAX10 TABLETA RECUBIERTA]]></cbc:Description>
<cac:SellersItemIdentification>
<cbc:ID>00128</cbc:ID>
</cac:SellersItemIdentification>
</cac:Item>
<cac:Price>
<cbc:PriceAmount currencyID="PEN">10.68000</cbc:PriceAmount>
</cac:Price>
</cac:InvoiceLine><cac:InvoiceLine>
<cbc:ID>3</cbc:ID>
<cbc:InvoicedQuantity unitCode="NIU">10.00</cbc:InvoicedQuantity>
<cbc:LineExtensionAmount currencyID="PEN">118.64</cbc:LineExtensionAmount>
<cac:PricingReference>
<cac:AlternativeConditionPrice>
<cbc:PriceAmount currencyID="PEN">14.00000</cbc:PriceAmount>
<cbc:PriceTypeCode>01</cbc:PriceTypeCode>
</cac:AlternativeConditionPrice>
</cac:PricingReference>
<cac:TaxTotal>
<cbc:TaxAmount currencyID="PEN">21.36</cbc:TaxAmount>
<cac:TaxSubtotal>
<cbc:TaxableAmount currencyID="PEN">118.64</cbc:TaxableAmount>
<cbc:TaxAmount currencyID="PEN">21.36</cbc:TaxAmount>
<cac:TaxCategory>
<cbc:Percent>18.00</cbc:Percent>
<cbc:TaxExemptionReasonCode>10</cbc:TaxExemptionReasonCode>
<cac:TaxScheme>
<cbc:ID>1000</cbc:ID>
<cbc:Name>IGV</cbc:Name>
<cbc:TaxTypeCode>VAT</cbc:TaxTypeCode>
</cac:TaxScheme>
</cac:TaxCategory>
</cac:TaxSubtotal>
</cac:TaxTotal>
<cac:Item>
<cbc:Description><![CDATA[AZBACT 500MG CAJAX10 TABLETAS RECUBIERTAS]]></cbc:Description>
<cac:SellersItemIdentification>
<cbc:ID>00129</cbc:ID>
</cac:SellersItemIdentification>
</cac:Item>
<cac:Price>
<cbc:PriceAmount currencyID="PEN">11.86000</cbc:PriceAmount>
</cac:Price>
</cac:InvoiceLine><cac:InvoiceLine>
<cbc:ID>4</cbc:ID>
<cbc:InvoicedQuantity unitCode="NIU">2.00</cbc:InvoicedQuantity>
<cbc:LineExtensionAmount currencyID="PEN">101.69</cbc:LineExtensionAmount>
<cac:PricingReference>
<cac:AlternativeConditionPrice>
<cbc:PriceAmount currencyID="PEN">60.00000</cbc:PriceAmount>
<cbc:PriceTypeCode>01</cbc:PriceTypeCode>
</cac:AlternativeConditionPrice>
</cac:PricingReference>
<cac:TaxTotal>
<cbc:TaxAmount currencyID="PEN">18.31</cbc:TaxAmount>
<cac:TaxSubtotal>
<cbc:TaxableAmount currencyID="PEN">101.69</cbc:TaxableAmount>
<cbc:TaxAmount currencyID="PEN">18.31</cbc:TaxAmount>
<cac:TaxCategory>
<cbc:Percent>18.00</cbc:Percent>
<cbc:TaxExemptionReasonCode>10</cbc:TaxExemptionReasonCode>
<cac:TaxScheme>
<cbc:ID>1000</cbc:ID>
<cbc:Name>IGV</cbc:Name>
<cbc:TaxTypeCode>VAT</cbc:TaxTypeCode>
</cac:TaxScheme>
</cac:TaxCategory>
</cac:TaxSubtotal>
</cac:TaxTotal>
<cac:Item>
<cbc:Description><![CDATA[LEVOFLOXACINO 500MG CAJA X 100 TAB RECUBIERTAS]]></cbc:Description>
<cac:SellersItemIdentification>
<cbc:ID>00288</cbc:ID>
</cac:SellersItemIdentification>
</cac:Item>
<cac:Price>
<cbc:PriceAmount currencyID="PEN">50.85000</cbc:PriceAmount>
</cac:Price>
</cac:InvoiceLine></Invoice>
Cuando necesito leer el dato del RUC del cliente de esta parte no encuentro como diferenciar ya que <cac:PartyIdentification> se encuenta en 3 partes
<cac:AccountingCustomerParty>
<cac:Party>
<cac:PartyIdentification>
<cbc:ID schemeID="6">20451640047</cbc:ID>
</cac:PartyIdentification>
<cac:PartyLegalEntity>
<cbc:RegistrationName><![CDATA[MEDICOS & FISIOTERAPEUTAS FISIOAPAIN E.I.R.L]]></cbc:RegistrationName>
<cac:RegistrationAddress>
<cac:AddressLine>
<cbc:Line><![CDATA[CAL.DANIEL OLAECHEA NRO. 260 DPTO. 504 URB. HUASCAR (CRUCE CON AV. INCA RIPAC)]]></cbc:Line>
</cac:AddressLine>
<cac:Country>
<cbc:IdentificationCode>PE</cbc:IdentificationCode>
</cac:Country>
</cac:RegistrationAddress>
</cac:PartyLegalEntity>
</cac:Party>
</cac:AccountingCustomerParty>