Option Explicit On
Option Strict On
Imports System.Data
Imports system.Data.SqlClient
Public Class NorthwindDataSet
Public Shared Sub Main()
Dim connectionString As String = _
GetConnectionString()
ConnectToData(connectionString)
End Sub
Private Shared Sub ConnectToData( _
ByVal connectionString As String)
' Create a SqlConnection to the Northwind database.
Using connection As SqlConnection = New SqlConnection( _
connectionString)
' Create a SqlDataAdapter for the Suppliers table.
Dim suppliersAdapter As SqlDataAdapter = _
New SqlDataAdapter()
' A table mapping names the DataTable.
suppliersAdapter.TableMappings.Add("Table", "Suppliers")
' Open the connection.
connection.Open()
Console.WriteLine("The SqlConnection is open.")
' Create a SqlCommand to retrieve Suppliers data.
Dim suppliersCommand As SqlCommand = New SqlCommand( _
"SELECT SupplierID, CompanyName FROM dbo.Suppliers;", _
connection)
suppliersCommand.CommandType = CommandType.Text
' Set the SqlDataAdapter's SelectCommand.
suppliersAdapter.SelectCommand = suppliersCommand
' Fill the DataSet.
Dim dataSet As DataSet = New DataSet("Suppliers")
suppliersAdapter.Fill(dataSet)
' Create a second SqlDataAdapter and SqlCommand to get
' the Products table, a child table of Suppliers.
Dim productsAdapter As SqlDataAdapter = _
New SqlDataAdapter()
productsAdapter.TableMappings.Add("Table", "Products")
Dim productsCommand As SqlCommand = New SqlCommand( _
"SELECT ProductID, SupplierID FROM dbo.Products;", _
connection)
productsAdapter.SelectCommand = productsCommand
' Fill the DataSet.
productsAdapter.Fill(dataSet)
' Close the connection.
connection.Close()
Console.WriteLine("The SqlConnection is closed.")
' Create a DataRelation to link the two tables
' based on the SupplierID.
Dim parentColumn As DataColumn = _
dataSet.Tables("Suppliers").Columns("SupplierID")
Dim childColumn As DataColumn = _
dataSet.Tables("Products").Columns("SupplierID")
Dim relation As DataRelation = New _
System.Data.DataRelation("SuppliersProducts", _
parentColumn, childColumn)
dataSet.Relations.Add(relation)
Console.WriteLine( _
"The {0} DataRelation has been created.", _
relation.RelationName)
End Using
End Sub
Private Shared Function GetConnectionString() As String
' To avoid storing the connection string in your code,
' you can retrieve it from a configuration file.
Return "Data Source=(local);Initial Catalog=Northwind;" _
& "Integrated Security=SSPI;"
End Function
End Class
using System;
using System.Data;
using System.Data.SqlClient;
namespace Microsoft.AdoNet.DataSetDemo
{
class NorthwindDataSet
{
static void Main()
{
string connectionString = GetConnectionString();
ConnectToData(connectionString);
}
private static void ConnectToData(string connectionString)
{
//Create a SqlConnection to the Northwind database.
using (SqlConnection connection =
new SqlConnection(connectionString))
{
//Create a SqlDataAdapter for the Suppliers table.
SqlDataAdapter adapter = new SqlDataAdapter();
// A table mapping names the DataTable.
adapter.TableMappings.Add("Table", "Suppliers");
// Open the connection.
connection.Open();
Console.WriteLine("The SqlConnection is open.");
// Create a SqlCommand to retrieve Suppliers data.
SqlCommand command = new SqlCommand(
"SELECT SupplierID, CompanyName FROM dbo.Suppliers;",
connection);
command.CommandType = CommandType.Text;
// Set the SqlDataAdapter's SelectCommand.
adapter.SelectCommand = command;
// Fill the DataSet.
DataSet dataSet = new DataSet("Suppliers");
adapter.Fill(dataSet);
// Create a second Adapter and Command to get
// the Products table, a child table of Suppliers.
SqlDataAdapter productsAdapter = new SqlDataAdapter();
productsAdapter.TableMappings.Add("Table", "Products");
SqlCommand productsCommand = new SqlCommand(
"SELECT ProductID, SupplierID FROM dbo.Products;",
connection);
productsAdapter.SelectCommand = productsCommand;
// Fill the DataSet.
productsAdapter.Fill(dataSet);
// Close the connection.
connection.Close();
Console.WriteLine("The SqlConnection is closed.");
// Create a DataRelation to link the two tables
// based on the SupplierID.
DataColumn parentColumn =
dataSet.Tables["Suppliers"].Columns["SupplierID"];
DataColumn childColumn =
dataSet.Tables["Products"].Columns["SupplierID"];
DataRelation relation =
new System.Data.DataRelation("SuppliersProducts",
parentColumn, childColumn);
dataSet.Relations.Add(relation);
Console.WriteLine(
"The {0} DataRelation has been created.",
relation.RelationName);
}
}
static private string GetConnectionString()
{
// To avoid storing the connection string in your code,
// you can retrieve it from a configuration file.
return "Data Source=(local);Initial Catalog=Northwind;"
+ "Integrated Security=SSPI";
}
}
}