Working with XML Data Sources Leave feedback

To access XML data while building a report, you can read XML into a DataSet and pass it to the assembler as a data source. However, if you cannot specify an XML schema while loading XML into a DataSet, all attributes and text values of XML elements are loaded as strings. Thus, it becomes impossible, for example, to use arithmetic operations on numbers or to specify custom date-time and numeric formats to output corresponding values, because all of them are treated as strings.

To overcome this limitation, pass an XmlDataSource instance to the assembler as a data source instead. Even when an XML schema is not provided, XmlDataSource recognizes values of the following types by their string representations:

• Integer
• Long
• Double
• Boolean
• Date

Warning

For recognition of data types to work, string representations of corresponding attributes and text values of XML elements must be formed using invariant culture settings.

An XmlDataSource can be created from a file path or a Java InputStream, optionally together with an XML schema and XmlDataLoadOptions.

In template documents, if a top-level XML element contains only a sequence of elements of the same type, an XmlDataSource instance should be treated in the same way as if it was a DataTable instance (see “Using Data Sources” for more information).

Suppose we have XML data like:

<Persons>
   <Person>
      <Name>John Doe</Name>
      <Age>30</Age>
      <Birth>1989-04-01 4:00:00 pm</Birth>
   </Person>
   <Person>
      <Name>Jane Doe</Name>
      <Age>27</Age>
      <Birth>1992-01-31 07:00:00 am</Birth>
   </Person>
   <Person>
      <Name>John Smith</Name>
      <Age>51</Age>
      <Birth>1968-03-08 1:00:00 pm</Birth>
   </Person>
</Persons>

And the following template:

<<foreach [in persons]>>Name: <<[Name]>>, Age: <<[Age]>>, Date of Birth: <<[Birth]:"dd.MM.yyyy">>
<</foreach>>
Average age: <<[persons.average(p => p.Age)]>>

The data source is passed under the name used in the template:

const groupdocs = require('@groupdocs/groupdocs.assembly');

const dataSource = new groupdocs.XmlDataSource("persons.xml");
const assembler = new groupdocs.DocumentAssembler();
assembler.assembleDocument("template.txt", "report.txt",
    new groupdocs.DataSourceInfo(dataSource, "persons"));

The result is:

Name: John Doe, Age: 30, Date of Birth: 01.04.1989
Name: Jane Doe, Age: 27, Date of Birth: 31.01.1992
Name: John Smith, Age: 51, Date of Birth: 08.03.1968

Average age: 36.0

Warning

Using a custom date-time format and an extension method involving arithmetic in the template is possible because text values of the Birth and Age XML elements are automatically converted to a date and an integer respectively, even in the absence of an XML schema.

If a top-level XML element contains attributes or nested elements of different types, an XmlDataSource instance should be treated in template documents in the same way as if it was a DataRow instance (see “Using Data Sources” for more information) as shown in the following example.

Suppose we have XML data like:

<Person>
   <Name>John Doe</Name>
   <Age>30</Age>
   <Birth>1989-04-01 4:00:00 pm</Birth>
   <Child>Ann Doe</Child>
   <Child>Charles Doe</Child>
</Person>

And the following template:

Name: <<[Name]>>, Age: <<[Age]>>, Date of Birth:
<<[Birth]:"dd.MM.yyyy">>
Children:
<<foreach [in Child]>><<[Child_Text]>>
<</foreach>>

The members of the element are referenced directly, so the data source can be passed without a name:

const dataSource = new groupdocs.XmlDataSource("person.xml");
assembler.assembleDocument("template.txt", "report.txt",
    new groupdocs.DataSourceInfo(dataSource));

The result is:

Name: John Doe, Age: 30, Date of Birth:
01.04.1989
Children:
Ann Doe
Charles Doe

Warning

To reference a sequence of repeated simple-type XML elements with the same name, use the elements’ name itself (for example, “Child”) in a template document, and the same name with the “_Text” suffix (for example, “Child_Text”) to reference the text value of one of these elements.

The following example sums up typical scenarios involving nested complex-type XML elements.

<Managers>
   <Manager>
      <Name>John Smith</Name>
      <Contract>
         <Client>
            <Name>A Company</Name>
         </Client>
         <Price>1200000</Price>
      </Contract>
      <Contract>
         <Client>
            <Name>B Ltd.</Name>
         </Client>
         <Price>750000</Price>
      </Contract>
      <Contract>
         <Client>
            <Name>C &amp; D</Name>
         </Client>
         <Price>350000</Price>
      </Contract>
   </Manager>
   <Manager>
      <Name>Tony Anderson</Name>
      <Contract>
         <Client>
            <Name>E Corp.</Name>
         </Client>
         <Price>650000</Price>
      </Contract>
      <Contract>
         <Client>
            <Name>F &amp; Partners</Name>
         </Client>
         <Price>550000</Price>
      </Contract>
   </Manager>
   <Manager>
      <Name>July James</Name>
      <Contract>
         <Client>
            <Name>G &amp; Co.</Name>
         </Client>
         <Price>350000</Price>
      </Contract>
      <Contract>
         <Client>
            <Name>H Group</Name>
         </Client>
         <Price>250000</Price>
      </Contract>
      <Contract>
         <Client>
            <Name>I &amp; Sons</Name>
         </Client>
         <Price>100000</Price>
      </Contract>
      <Contract>
         <Client>
            <Name>J Ent.</Name>
         </Client>
         <Price>100000</Price>
      </Contract>
   </Manager>
</Managers>

<<foreach [in managers]>>Manager: <<[Name]>>
Contracts:
<<foreach [in Contract]>>- <<[Client.Name]>> ($<<[Price]>>)
<</foreach>>
<</foreach>>

const groupdocs = require('@groupdocs/groupdocs.assembly');

// Source template and destination report
const templatePath = "SimpleDatasetDemo.docx";
const reportPath = "SimpleXMLDSDemo Out.docx";

// Load the XML data
const dataSource = new groupdocs.XmlDataSource("Managers.xml");
const dataSourceInfo = new groupdocs.DataSourceInfo(dataSource, "managers");

// Assemble the document
const assembler = new groupdocs.DocumentAssembler();
assembler.assembleDocument(templatePath, reportPath, dataSourceInfo);

process.exit(0);

Manager: John Smith
Contracts:
- A Company ($1200000)
- B Ltd. ($750000)
- C & D ($350000)
Manager: Tony Anderson
Contracts:
- E Corp. ($650000)
- F & Partners ($550000)
Manager: July James
Contracts:
- G & Co. ($350000)
- H Group ($250000)
- I & Sons ($100000)
- J Ent. ($100000)

• Managers.xml

• SimpleDatasetDemo.docx