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In a section report, you can modify your data source at run time. Follow the steps below to connect your report to the NWind.mdb sample database at run time.

To find the database path

Note: These steps assume that the data path is defined in the following registry key.

1. Right-click the design surface, and select View Code to display the code view for the report.
2. Add the following code to the report to access the sample database path from the registry.

To write the code in Visual Basic

Imports System 
Imports Microsoft.Win32

Private Function getDatabasePath() As String
               
End Function

Dim regKey As RegistryKey
regKey = Registry.LocalMachine
regKey = regKey.CreateSubKey("SOFTWARE\\ComponentOne\\ActiveReports\\v8")
getDatabasePath = CType(regKey.GetValue(""), String)

To write the code in C#

using Microsoft.Win32;
using System;

private string getDatabasePath()

{
RegistryKey regKey = Registry.LocalMachine;
regKey = regKey.CreateSubKey("SOFTWARE\\ComponentOne\\ActiveReports\\v8");
return ((string)(regKey.GetValue("")));
}

To change the data source at run time

1. Double-click the gray area outside the design surface to create an event-handling method for the ReportStart event.
2. Add the following code to the handler to change the data source at run time.

To write the code in Visual Basic.NET

Dim conn As System.Data.OleDb.OleDbConnection
Dim reader As System.Data.OleDb.OleDbDataReader

Dim dbPath As String = getDatabasePath()
Dim connString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + dbPath + "\NWIND.mdb"
conn = New System.Data.OleDb.OleDbConnection(connString)     
Dim cmd As New System.Data.OleDb.OleDbCommand("SELECT * FROM Products WHERE UnitPrice = 18", conn)
conn.Open()
reader = cmd.ExecuteReader()
Me.DataSource = reader

To write the code in C#

private static System.Data.OleDb.OleDbConnection conn;
private static System.Data.OleDb.OleDbDataReader reader;

string dbPath = getDatabasePath();
string connString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + dbPath + "\\NWIND.mdb";
conn = new System.Data.OleDb.OleDbConnection(connString);
System.Data.OleDb.OleDbCommand cmd = new System.Data.OleDb.OleDbCommand("SELECT * FROM Products WHERE UnitPrice = 18", conn);
conn.Open();
reader = cmd.ExecuteReader();
this.DataSource = reader;

To close the data connection

1. Right-click the gray area outside the design surface and select Properties.
2. In the Properties Window that appears, click the Events button. A list of report events appear.
3. Select the ReportEnd event and double click to create an event-handling method.
4. Add the following code to the handler to close the data connection.

To write the code in Visual Basic

reader.Close()
conn.Close()

To write the code in C#

reader.Close();
conn.Close();