HOW TO: Programmatically Create a Hierarchical DataSet Object with ADO.NET in Visual Basic .NET (316260)

SUMMARY

This step-by-step article describes how to create a hierarchical DataSet object that you can use as a structure for your programs. You may not have the exact data or structure that you want to use for your project. You can use the method in this article to create prototypes for your examples. It may also be easier to submit only the data that you do have to the database without using the shape command syntax to send the data to the database. You might also have a limited set of data that you must add to the database. Instead of passing 20 arguments about the data to a method, you can pass the programmatically created DataSet object. This article describes how to use this method.

This example in this article creates a new customer and creates related order information, and outputs the data as XML. You start by defining the DataSet object, and then create two tables and a row. Then, you define the columns, add a relationship between the tables, fill the rows with data, append rows to the rows collection, and present the data in XML format.

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Requirements

The following list outlines the recommended hardware, software, network infrastructure, and service packs that are required:

• Microsoft Visual Studio .NET installed on a compatible Microsoft Windows operating system

This article assumes that you are familiar with the following topics:

• Visual Basic .NET
• ADO.NET data access

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Create the Project

1. Start Visual Studio .NET, and then create a new Visual Basic .NET Console application.
2. Add the following IMPORTS statements to the top of the code window:

   Imports System
   Imports System.Data
   Imports System.XML
   					

3. In the Sub Main section, add the following code:

    
           Dim myDS As New Data.DataSet("CusOrd")
           Dim myCustomers As Data.DataTable = myDS.Tables.Add("Customers")
           Dim myOrders As Data.DataTable = myDS.Tables.Add("Orders")
           Dim myDr As Data.DataRow
   
           With myCustomers
               .Columns.Add("CustomerID", Type.GetType("System.String"))
               .Columns.Add("CompanyName", Type.GetType("System.String"))
               .Columns.Add("ContactName", Type.GetType("System.String"))
           End With
   
           With myOrders
               .Columns.Add("OrderID", Type.GetType("System.Int32"))
               .Columns.Add("CustomerID", Type.GetType("System.String"))
               .Columns.Add("EmployeeID", Type.GetType("System.Int32"))
               .Columns.Add("OrderDate", Type.GetType("System.DateTime"))
               .Columns.Add("RequiredDate", Type.GetType("System.DateTime"))
           End With
   
   
           myDS.Relations.Add("rel_Customers_Orders", _
           myDS.Tables("Customers").Columns("CustomerID"), _
           myDS.Tables("Orders").Columns("CustomerID"))
   
           myDr = myCustomers.NewRow()
           myDr("CustomerID") = "9876"
           myDr("CompanyName") = "Lucerne Publishing"
           myDr("ContactName") = "Kim Ralls"       
   
           myCustomers.Rows.Add(myDr)
   
           myDr = myOrders.NewRow()
           myDr("OrderID") = 6521
           myDr("CustomerID") = "9876"
           myDr("EmployeeID") = 852
           myDr("OrderDate") = #1/5/2002#
           myDr("RequiredDate") = #2/1/2002#
           myOrders.Rows.Add(myDr)
   
           Console.WriteLine(myDS.GetXml())
   					

4. Press CTRL+F5 to run the application and observe the output.

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