Working with XML Data Sources Leave feedback

Note

This feature is only compatible with GroupDocs.Assembly for Java 19.10 or later releases.

To access XML data while building a report, you can use facilities of DataSet to read XML into it and then pass it to the assembler as a data source. However, if your scenario does not permit to specify XML schema while loading XML into DataSet, all attributes and text values of XML elements are loaded as strings then. Thus, it becomes impossible, for example, to use arithmetic operations on numbers or to specify custom date-time and numeric formats to output orresponding values, because all of them are treated as strings. To overcome this limitation, you can pass an XmlDataSource instance to the assembler as a data source instead. Even when XML schema is not provided, XmlDataSource is capable to recognize values of the following types by their string representations:

• Int32?
• Int64?
• Double?
• Boolean?
• DateTime?

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.

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 “Working with DataTable and DataView Objects” 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>

By using the template like following:

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

The results will be produced like:

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

Warning

Using of the custom date-time format and the extension method involving arithmetic in the template document becomes possible, because text values of Birth and Age XML elements are automatically converted to DateTime? and Int32? respectively even in the absence of 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 “Working with DataRow and DataRowView Objects” 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>

By using the template like following:

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

The results will be produced like:

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, the elements’ name itself (for example, “Child”) should be used in a template document, whereas the same name with the “_Text” suffix (for example, “Child_Text”) should be used 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>
            43
         </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>>

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