serializable datatables and web services in ado.net 2.0

In ado.net 2.0, datatables are serializable (grin grin grin) so that means you can return them from a web service (though you must fill the tablename property first). Below is what the xml looks like (compared below that, to what the same table looks look like  in a dataset)

Not much difference here. But it creates a few less steps on both the web service end and the client end and it bridges a gap for developers. I wonder how many of us tried to return a datatable from a webservice because we didn’t understand the depths of xml serialization and that datatable, up until now, did not implement iSerializable. And then had to do a bit of digging before we found a sentence somewhere that explained that you need to return the dataset. So we save some coding, but also a whole lot of figgerin’ for those folks who don’t need to grok soap and serialization just to move some data around.

 <?xml version=”1.0″ encoding=”utf-8″ ?>

<DataTable xmlns=”http://tempuri.org/>
<xs:schema id=”NewDataSet xmlns=” xmlns:xs=”http://www.w3.org/2001/XMLSchema xmlns:msdata=”urn:schemas-microsoft-com:xml-msdata>
<xs:element name=”NewDataSet msdata:IsDataSet=”true msdata:MainDataTable=”julietable>
<xs:complexType>
<xs:choice minOccurs=”0 maxOccurs=”unbounded>
<xs:element name=”julietable>
<xs:complexType>
<xs:sequence>
  <xs:element name=”au_id type=”xs:string minOccurs=”0 />
  <xs:element name=”au_lname type=”xs:string minOccurs=”0 />
  <xs:element name=”au_fname type=”xs:string minOccurs=”0 />
  <xs:element name=”phone type=”xs:string minOccurs=”0 />
  <xs:element name=”address type=”xs:string minOccurs=”0 />
  <xs:element name=”city type=”xs:string minOccurs=”0 />
  <xs:element name=”state type=”xs:string minOccurs=”0 />
  <xs:element name=”zip type=”xs:string minOccurs=”0 />
  <xs:element name=”contract type=”xs:boolean minOccurs=”0 />
  </xs:sequence>
  </xs:complexType>
  </xs:element>
  </xs:choice>
  </xs:complexType>
  </xs:element>
  </xs:schema>
<diffgr:diffgram xmlns:msdata=”urn:schemas-microsoft-com:xml-msdata xmlns:diffgr=”urn:schemas-microsoft-com:xml-diffgram-v1>
<DocumentElement xmlns=”>
<julietable diffgr:id=”julietable1 msdata:rowOrder=”0>
  <au_id>172-32-1176</au_id>
  <au_lname>White</au_lname>
  <au_fname>chris</au_fname>
  <phone>408 222-1229</phone>
  <address>10932 Bigge Rd.</address>
  <city>Menlo Park</city>
  <state>CA</state>
  <zip>94025</zip>
  <contract>true</contract>
  </julietable>
  </DocumentElement>
  </diffgr:diffgram>
  </DataTable>

————————

  <?xml version=”1.0″ encoding=”utf-8″ ?>
<DataSet xmlns=”http://tempuri.org/>
<xs:schema id=”NewDataSet xmlns=” xmlns:xs=”http://www.w3.org/2001/XMLSchema xmlns:msdata=”urn:schemas-microsoft-com:xml-msdata>
<xs:element name=”NewDataSet msdata:IsDataSet=”true>
<xs:complexType>
<xs:choice minOccurs=”0 maxOccurs=”unbounded>
<xs:element name=”julietable>
<xs:complexType>
<xs:sequence>
  <xs:element name=”au_id type=”xs:string minOccurs=”0 />
  <xs:element name=”au_lname type=”xs:string minOccurs=”0 />
  <xs:element name=”au_fname type=”xs:string minOccurs=”0 />
  <xs:element name=”phone type=”xs:string minOccurs=”0 />
  <xs:element name=”address type=”xs:string minOccurs=”0 />
  <xs:element name=”city type=”xs:string minOccurs=”0 />
  <xs:element name=”state type=”xs:string minOccurs=”0 />
  <xs:element name=”zip type=”xs:string minOccurs=”0 />
  <xs:element name=”contract type=”xs:boolean minOccurs=”0 />
  </xs:sequence>
  </xs:complexType>
  </xs:element>
  </xs:choice>
  </xs:complexType>
  </xs:element>
  </xs:schema>
<diffgr:diffgram xmlns:msdata=”urn:schemas-microsoft-com:xml-msdata xmlns:diffgr=”urn:schemas-microsoft-com:xml-diffgram-v1>
<NewDataSet xmlns=”>
<julietable diffgr:id=”julietable1 msdata:rowOrder=”0>
  <au_id>172-32-1176</au_id>
  <au_lname>White</au_lname>
  <au_fname>chris</au_fname>
  <phone>408 222-1229</phone>
  <address>10932 Bigge Rd.</address>
  <city>Menlo Park</city>
  <state>CA</state>
  <zip>94025</zip>
  <contract>true</contract>
  </julietable>
</NewDataSet>
  </diffgr:diffgram>
  </DataSet>

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