Cómo: Compartir datos enlazados entre formularios mediante el componente BindingSource
Actualización: noviembre 2007
Es fácil compartir datos entre formularios mediante el componente BindingSource. Por ejemplo, quizás desee mostrar un formulario de sólo lectura que resuma los datos del origen de datos y otro formulario que se pueda modificar que contenga información detallada acerca del elemento actualmente seleccionado en el origen de datos. En este ejemplo se muestra este escenario.
Ejemplo
En el ejemplo de código siguiente se muestra cómo compartir un componente BindingSource y los datos enlazados entre formularios. En este ejemplo, se pasa el componente BindingSource compartido al constructor del formulario secundario. El formulario secundario permite al usuario editar los datos del elemento actualmente seleccionado en el formulario principal.
.gif "Nota") Nota: |
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En el ejemplo se controla el evento BindingComplete del componente BindingSource para garantizar que los dos formularios permanecen sincronizados. Para obtener más información sobre las razones, vea Cómo: Garantizar que varios controles enlazados al mismo origen de datos permanezcan sincronizados. |
Imports System
Imports System.Drawing
Imports System.Windows.Forms
Imports System.Data
Public Class MainForm
Inherits Form
Public Sub New()
End Sub
Private WithEvents bindingSource1 As BindingSource
Private WithEvents button1 As Button
Private Sub MainForm_Load(ByVal sender As Object, ByVal e As EventArgs) _
Handles Me.Load
InitializeData()
End Sub
Private Sub InitializeData()
bindingSource1 = New System.Windows.Forms.BindingSource()
Dim dataset1 As New DataSet()
ClientSize = New System.Drawing.Size(292, 266)
' Some xml data to populate the DataSet with.
' Some xml data to populate the DataSet with.
Dim musicXml As String = "<?xml version='1.0' encoding='UTF-8'?>" & _
"<music><recording><artist>Dave Matthews</artist>" & _
"<cd>Under the Table and Dreaming</cd>" & _
"<releaseDate>1994</releaseDate><rating>3.5</rating></recording>" & _
"<recording><artist>Coldplay</artist><cd>X&Y</cd>" & _
"<releaseDate>2005</releaseDate><rating>4</rating></recording>" & _
"<recording><artist>Dave Matthews</artist>" & _
"<cd>Live at Red Rocks</cd>" & _
"<releaseDate>1997</releaseDate><rating>4</rating></recording>" & _
"<recording><artist>U2</artist>" & _
"<cd>Joshua Tree</cd><releaseDate>1987</releaseDate>" & _
"<rating>5</rating></recording>" & _
"<recording><artist>U2</artist>" & _
"<cd>How to Dismantle an Atomic Bomb</cd>" & _
"<releaseDate>2004</releaseDate><rating>4.5</rating></recording>" & _
"<recording><artist>Natalie Merchant</artist>" & _
"<cd>Tigerlily</cd><releaseDate>1995</releaseDate>" & _
"<rating>3.5</rating></recording>" & _
"</music>"
' Read the xml.
Dim reader As New System.IO.StringReader(musicXml)
dataset1.ReadXml(reader)
' Get a DataView of the table contained in the dataset.
Dim tables As DataTableCollection = dataset1.Tables
Dim view1 As New DataView(tables(0))
' Create a DataGridView control and add it to the form.
Dim datagridview1 As New DataGridView()
datagridview1.ReadOnly = True
datagridview1.AutoGenerateColumns = True
datagridview1.Width = 300
Me.Controls.Add(datagridview1)
bindingSource1.DataSource = view1
datagridview1.DataSource = bindingSource1
datagridview1.Columns.Remove("artist")
datagridview1.Columns.Remove("releaseDate")
' Create and add a button to the form.
button1 = New Button()
button1.AutoSize = True
button1.Text = "Show/Edit Details"
Me.Controls.Add(button1)
button1.Location = New Point(50, 200)
End Sub
' Handle the BindingComplete event to ensure the two forms
' remain synchronized.
Private Sub bindingSource1_BindingComplete(ByVal sender As Object, _
ByVal e As BindingCompleteEventArgs) Handles bindingSource1.BindingComplete
If e.BindingCompleteContext = BindingCompleteContext.DataSourceUpdate _
AndAlso e.Exception Is Nothing Then
e.Binding.BindingManagerBase.EndCurrentEdit()
End If
End Sub
' The detailed form will be shown when the button is clicked.
Private Sub button1_Click(ByVal sender As Object, ByVal e As EventArgs) _
Handles button1.Click
Dim detailForm As New DetailForm(bindingSource1)
detailForm.Show()
End Sub
<STAThread()> _
Shared Sub Main()
Application.EnableVisualStyles()
Application.Run(New MainForm())
End Sub
End Class
' The detail form class.
Public Class DetailForm
Inherits Form
Private formDataSource As BindingSource
' The constructor takes a BindingSource object.
Public Sub New(ByVal dataSource As BindingSource)
formDataSource = dataSource
Me.ClientSize = New Size(240, 200)
Dim textBox1 As New TextBox()
Me.Text = "Selection Details"
textBox1.Width = 220
Dim textBox2 As New TextBox()
Dim textBox3 As New TextBox()
Dim textBox4 As New TextBox()
textBox4.Width = 30
textBox3.Width = 50
' Associate each text box with a column from the data source.
textBox1.DataBindings.Add("Text", formDataSource, "cd", _
True, DataSourceUpdateMode.OnPropertyChanged)
textBox2.DataBindings.Add("Text", formDataSource, "artist", True)
textBox3.DataBindings.Add("Text", formDataSource, "releaseDate", True)
textBox4.DataBindings.Add("Text", formDataSource, "rating", True)
textBox1.Location = New Point(10, 10)
textBox2.Location = New Point(10, 40)
textBox3.Location = New Point(10, 80)
textBox4.Location = New Point(10, 120)
Me.Controls.AddRange(New Control() {textBox1, textBox2, textBox3, _
textBox4})
End Sub
End Class
using System;
using System.Drawing;
using System.Windows.Forms;
using System.Data;
namespace BindingSourceMultipleForms
{
public class MainForm : Form
{
public MainForm()
{
this.Load += new EventHandler(MainForm_Load);
}
private BindingSource bindingSource1;
private Button button1;
private void MainForm_Load(object sender, EventArgs e)
{
InitializeData();
}
private void InitializeData()
{
bindingSource1 = new System.Windows.Forms.BindingSource();
// Handle the BindingComplete event to ensure the two forms
// remain synchronized.
bindingSource1.BindingComplete +=
new BindingCompleteEventHandler(bindingSource1_BindingComplete);
ClientSize = new System.Drawing.Size(292, 266);
DataSet dataset1 = new DataSet();
// Some xml data to populate the DataSet with.
string musicXml =
"<?xml version='1.0' encoding='UTF-8'?>" +
"<music>" +
"<recording><artist>Dave Matthews</artist>" +
"<cd>Under the Table and Dreaming</cd>" +
"<releaseDate>1994</releaseDate><rating>3.5</rating></recording>" +
"<recording><artist>Coldplay</artist><cd>X&Y</cd>" +
"<releaseDate>2005</releaseDate><rating>4</rating></recording>" +
"<recording><artist>Dave Matthews</artist>" +
"<cd>Live at Red Rocks</cd>" +
"<releaseDate>1997</releaseDate><rating>4</rating></recording>" +
"<recording><artist>U2</artist>" +
"<cd>Joshua Tree</cd><releaseDate>1987</releaseDate>" +
"<rating>5</rating></recording>" +
"<recording><artist>U2</artist>" +
"<cd>How to Dismantle an Atomic Bomb</cd>" +
"<releaseDate>2004</releaseDate><rating>4.5</rating></recording>" +
"<recording><artist>Natalie Merchant</artist>" +
"<cd>Tigerlily</cd><releaseDate>1995</releaseDate>" +
"<rating>3.5</rating></recording>" +
"</music>";
// Read the xml.
System.IO.StringReader reader = new System.IO.StringReader(musicXml);
dataset1.ReadXml(reader);
// Get a DataView of the table contained in the dataset.
DataTableCollection tables = dataset1.Tables;
DataView view1 = new DataView(tables[0]);
// Create a DataGridView control and add it to the form.
DataGridView datagridview1 = new DataGridView();
datagridview1.ReadOnly = true;
datagridview1.AutoGenerateColumns = true;
datagridview1.Width = 300;
this.Controls.Add(datagridview1);
bindingSource1.DataSource = view1;
datagridview1.DataSource = bindingSource1;
datagridview1.Columns.Remove("artist");
datagridview1.Columns.Remove("releaseDate");
// Create and add a button to the form.
button1 = new Button();
button1.AutoSize = true;
button1.Text = "Show/Edit Details";
this.Controls.Add(button1);
button1.Location = new Point(50, 200);
button1.Click += new EventHandler(button1_Click);
}
// Handle the BindingComplete event to ensure the two forms
// remain synchronized.
private void bindingSource1_BindingComplete(object sender, BindingCompleteEventArgs e)
{
if (e.BindingCompleteContext == BindingCompleteContext.DataSourceUpdate
&& e.Exception == null)
e.Binding.BindingManagerBase.EndCurrentEdit();
}
// The detailed form will be shown when the button is clicked.
private void button1_Click(object sender, EventArgs e)
{
DetailForm detailForm = new DetailForm(bindingSource1);
detailForm.Show();
}
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.Run(new MainForm());
}
}
// The detail form class.
public class DetailForm : Form
{
private BindingSource formDataSource;
// The constructor takes a BindingSource object.
public DetailForm(BindingSource dataSource)
{
formDataSource = dataSource;
this.ClientSize = new Size(240, 200);
TextBox textBox1 = new TextBox();
this.Text = "Selection Details";
textBox1.Width = 220;
TextBox textBox2 = new TextBox();
TextBox textBox3 = new TextBox();
TextBox textBox4 = new TextBox();
textBox4.Width = 30;
textBox3.Width = 50;
// Associate each text box with a column from the data source.
textBox1.DataBindings.Add("Text", formDataSource, "cd", true, DataSourceUpdateMode.OnPropertyChanged);
textBox2.DataBindings.Add("Text", formDataSource, "artist", true);
textBox3.DataBindings.Add("Text", formDataSource, "releaseDate", true);
textBox4.DataBindings.Add("Text", formDataSource, "rating", true);
textBox1.Location = new Point(10, 10);
textBox2.Location = new Point(10, 40);
textBox3.Location = new Point(10, 80);
textBox4.Location = new Point(10, 120);
this.Controls.AddRange(new Control[] { textBox1, textBox2, textBox3, textBox4 });
}
}
}
Compilar el código
Este ejemplo requiere:
- Referencias a los ensamblados System, System.Windows.Forms, System.Drawing, System.Data y System.Xml.
Para obtener información acerca de la generación de este ejemplo desde la línea de comandos de Visual Basic o Visual C#, vea Generar desde la línea de comandos (Visual Basic) o Generar la línea de comandos con csc.exe. También puede generar este ejemplo en Visual Studio pegando el código en un proyecto nuevo.
Vea también
Tareas
Cómo: Controlar errores y excepciones que se producen con el enlace de datos