Re: Convert an untyped Data Table to a typed Data Table

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John Wright wrote:
I need to convert some of my untyped datatables to typed datatables. Is
there a way to do this? I am assuming I need to convert the table to XML
then back, but I am unsure. Does anyone have any code or can point me in the
right direciton? I really appreciate the help.

The easier and most flexible solution (IMHO) is the dataset designer
which will generate a dataset with datatables built after the schemma
of an existing database. It will create the dataset, the datatables,
the relations between the tables and even the table adapters.

If you have the datatables but no database, you may use the xsd.exe
utility (in my setup it lives in %programfiles%\Microsoft Visual
Studio 8\SDK\v2.0\Bin"). This utility will practically mimic the work
of the designer (except for not automagically creating the table
adapters). It feeds on XSD files and generates datasets (or classes)
based on that. The nice touch is that it can create a XSD file based
on a sample XML file.

For example, given the following Dept.xml file:

<Dept>
<Employee>
<Id>10</Id>
<Name>Jack</Name>
</Employee>
<JobType>
<Id>1</Id>
<Name>Director</Name>
</JobType>
</Dept>

after executing "xsd Dept.xml", a Dept.xsd file is created (beware
word wrap):

<?xml version="1.0" encoding="utf-8"?>
<xs:schema id="Dept" xmlns="" xmlns:xs="http://www.w3.org/2001/
XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
<xs:element name="Dept" msdata:IsDataSet="true"; msdata:Locale="en-
US">
<xs:complexType>
<xs:choice minOccurs="0" maxOccurs="unbounded">
<xs:element name="Employee">
<xs:complexType>
<xs:sequence>
<xs:element name="Id" type="xs:string" minOccurs="0" />
<xs:element name="Name" type="xs:string" minOccurs="0" /

</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="JobType">
<xs:complexType>
<xs:sequence>
<xs:element name="Id" type="xs:string" minOccurs="0" />
<xs:element name="Name" type="xs:string" minOccurs="0" /

</xs:sequence>
</xs:complexType>
</xs:element>
</xs:choice>
</xs:complexType>
</xs:element>
</xs:schema>

You may edit the XSD to your liking (for example, changing the type
attribute of both Id columns from "xs:string" to xs:int"). Afterwards,
executing "xsd Dept.xsd /dataset /language:VB" generates the Dept.vb
file, containing the declaration for a strongly typed "Dept" dataset
as well as the two strongly typed tables "Employee" and "JobType".
Maybe the resulting code isn't pretty enough to your tastes (it isn't
to mine), but it makes a stepping stone for your further edits.

HTH.

Regards,

Branco.
.

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