Procedura: creare un form Master-Details mediante due controlli DataGridView di Windows Form
Aggiornamento: novembre 2007
Nell'esempio di codice riportato di seguito viene creato un form Master-Details utilizzando due controlli DataGridView associati a due componenti BindingSource. L'origine dati è un DataSet contenente le tabelle Customers e Orders del database di esempio SQL Server Northwind insieme a un DataRelation che mette in relazione le due tabelle attraverso la colonna CustomerID.
Un BindingSource è associato alla tabella Customers padre nel DataSet. Questi dati vengono visualizzati nel controllo DataGridView master. L'altro BindingSource è associato al primo connettore di dati. Poiché la proprietà DataMember del secondo BindingSource è impostata sul nome di DataRelation, il controllo DataGridView dettagli associato visualizza le righe della tabella Orders figlio corrispondenti alla riga corrente nel controllo DataGridView master.
Per una spiegazione completa dell'esempio di codice, vedere Procedura dettagliata: creazione di un form Master-Details mediante due controlli DataGridView Windows Form.
Esempio
Imports System
Imports System.Data
Imports System.Data.SqlClient
Imports System.Windows.Forms
Public Class Form1
Inherits System.Windows.Forms.Form
Private masterDataGridView As New DataGridView()
Private masterBindingSource As New BindingSource()
Private detailsDataGridView As New DataGridView()
Private detailsBindingSource As New BindingSource()
<STAThreadAttribute()> _
Public Shared Sub Main()
Application.Run(New Form1())
End Sub
' Initializes the form.
Public Sub New()
masterDataGridView.Dock = DockStyle.Fill
detailsDataGridView.Dock = DockStyle.Fill
Dim splitContainer1 As New SplitContainer()
splitContainer1.Dock = DockStyle.Fill
splitContainer1.Orientation = Orientation.Horizontal
splitContainer1.Panel1.Controls.Add(masterDataGridView)
splitContainer1.Panel2.Controls.Add(detailsDataGridView)
Me.Controls.Add(splitContainer1)
Me.Text = "DataGridView master/detail demo"
End Sub
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) _
Handles Me.Load
' Bind the DataGridView controls to the BindingSource
' components and load the data from the database.
masterDataGridView.DataSource = masterBindingSource
detailsDataGridView.DataSource = detailsBindingSource
GetData()
' Resize the master DataGridView columns to fit the newly loaded data.
masterDataGridView.AutoResizeColumns()
' Configure the details DataGridView so that its columns automatically
' adjust their widths when the data changes.
detailsDataGridView.AutoSizeColumnsMode = _
DataGridViewAutoSizeColumnsMode.AllCells
End Sub
Private Sub GetData()
Try
' Specify a connection string. Replace the given value with a
' valid connection string for a Northwind SQL Server sample
' database accessible to your system.
Dim connectionString As String = _
"Integrated Security=SSPI;Persist Security Info=False;" & _
"Initial Catalog=Northwind;Data Source=localhost"
Dim connection As New SqlConnection(connectionString)
' Create a DataSet.
Dim data As New DataSet()
data.Locale = System.Globalization.CultureInfo.InvariantCulture
' Add data from the Customers table to the DataSet.
Dim masterDataAdapter As _
New SqlDataAdapter("select * from Customers", connection)
masterDataAdapter.Fill(data, "Customers")
' Add data from the Orders table to the DataSet.
Dim detailsDataAdapter As _
New SqlDataAdapter("select * from Orders", connection)
detailsDataAdapter.Fill(data, "Orders")
' Establish a relationship between the two tables.
Dim relation As New DataRelation("CustomersOrders", _
data.Tables("Customers").Columns("CustomerID"), _
data.Tables("Orders").Columns("CustomerID"))
data.Relations.Add(relation)
' Bind the master data connector to the Customers table.
masterBindingSource.DataSource = data
masterBindingSource.DataMember = "Customers"
' Bind the details data connector to the master data connector,
' using the DataRelation name to filter the information in the
' details table based on the current row in the master table.
detailsBindingSource.DataSource = masterBindingSource
detailsBindingSource.DataMember = "CustomersOrders"
Catch ex As SqlException
MessageBox.Show("To run this example, replace the value of the " & _
"connectionString variable with a connection string that is " & _
"valid for your system.")
End Try
End Sub
End Class
using System;
using System.Data;
using System.Data.SqlClient;
using System.Windows.Forms;
public class Form1 : System.Windows.Forms.Form
{
private DataGridView masterDataGridView = new DataGridView();
private BindingSource masterBindingSource = new BindingSource();
private DataGridView detailsDataGridView = new DataGridView();
private BindingSource detailsBindingSource = new BindingSource();
[STAThreadAttribute()]
public static void Main()
{
Application.Run(new Form1());
}
// Initializes the form.
public Form1()
{
masterDataGridView.Dock = DockStyle.Fill;
detailsDataGridView.Dock = DockStyle.Fill;
SplitContainer splitContainer1 = new SplitContainer();
splitContainer1.Dock = DockStyle.Fill;
splitContainer1.Orientation = Orientation.Horizontal;
splitContainer1.Panel1.Controls.Add(masterDataGridView);
splitContainer1.Panel2.Controls.Add(detailsDataGridView);
this.Controls.Add(splitContainer1);
this.Load += new System.EventHandler(Form1_Load);
this.Text = "DataGridView master/detail demo";
}
private void Form1_Load(object sender, System.EventArgs e)
{
// Bind the DataGridView controls to the BindingSource
// components and load the data from the database.
masterDataGridView.DataSource = masterBindingSource;
detailsDataGridView.DataSource = detailsBindingSource;
GetData();
// Resize the master DataGridView columns to fit the newly loaded data.
masterDataGridView.AutoResizeColumns();
// Configure the details DataGridView so that its columns automatically
// adjust their widths when the data changes.
detailsDataGridView.AutoSizeColumnsMode =
DataGridViewAutoSizeColumnsMode.AllCells;
}
private void GetData()
{
try
{
// Specify a connection string. Replace the given value with a
// valid connection string for a Northwind SQL Server sample
// database accessible to your system.
String connectionString =
"Integrated Security=SSPI;Persist Security Info=False;" +
"Initial Catalog=Northwind;Data Source=localhost";
SqlConnection connection = new SqlConnection(connectionString);
// Create a DataSet.
DataSet data = new DataSet();
data.Locale = System.Globalization.CultureInfo.InvariantCulture;
// Add data from the Customers table to the DataSet.
SqlDataAdapter masterDataAdapter = new
SqlDataAdapter("select * from Customers", connection);
masterDataAdapter.Fill(data, "Customers");
// Add data from the Orders table to the DataSet.
SqlDataAdapter detailsDataAdapter = new
SqlDataAdapter("select * from Orders", connection);
detailsDataAdapter.Fill(data, "Orders");
// Establish a relationship between the two tables.
DataRelation relation = new DataRelation("CustomersOrders",
data.Tables["Customers"].Columns["CustomerID"],
data.Tables["Orders"].Columns["CustomerID"]);
data.Relations.Add(relation);
// Bind the master data connector to the Customers table.
masterBindingSource.DataSource = data;
masterBindingSource.DataMember = "Customers";
// Bind the details data connector to the master data connector,
// using the DataRelation name to filter the information in the
// details table based on the current row in the master table.
detailsBindingSource.DataSource = masterBindingSource;
detailsBindingSource.DataMember = "CustomersOrders";
}
catch (SqlException)
{
MessageBox.Show("To run this example, replace the value of the " +
"connectionString variable with a connection string that is " +
"valid for your system.");
}
}
}
Compilazione del codice
L'esempio presenta i seguenti requisiti:
- Riferimenti agli assembly System, System.Data, System.Windows.Forms e System.XML.
Per informazioni sulla compilazione di questo esempio dalla riga di comando per Visual Basic o Visual C#, vedere Compilazione dalla riga di comando (Visual Basic) o Compilazione dalla riga di comando con csc.exe. È anche possibile generare questo esempio in Visual Studio incollando il codice in un nuovo progetto.
Sicurezza
L'archiviazione delle informazioni riservate, ad esempio la password, nella stringa di connessione può avere implicazioni sulla sicurezza dell'applicazione. L'autenticazione, o sicurezza integrata, di Windows consente di controllare l'accesso a un database in modo più sicuro. Per ulteriori informazioni, vedere Protezione delle informazioni di connessione (ADO.NET).
Vedere anche
Attività
Concetti
Protezione delle informazioni di connessione (ADO.NET)
Riferimenti
Altre risorse
Visualizzazione di dati nel controllo DataGridView Windows Form