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>

<address>10932 Bigge Rd.</address>

<city>Menlo Park</city>

</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“>