Procedimiento para enlazar un control de formularios Windows Forms a un tipoHow to: Bind a Windows Forms Control to a Type

Al crear controles que interactúan con datos, a veces necesitará enlazar un control a un tipo en lugar de a un objeto.When you are building controls that interact with data, you will sometimes find it necessary to bind a control to a type, rather than an object. Estas situaciones se producen especialmente en tiempo de diseño, cuando puede que los datos no estén disponibles pero los controles enlazados a datos necesitan mostrar la información de una interfaz pública del tipo.This situation arises especially at design time, when data may not be available, but your data-bound controls still need to display information from a type's public interface. Por ejemplo, puede enlazar un control DataGridView a un objeto expuesto por un servicio Web y quiere que el control DataGridView etiquete sus columnas en tiempo de diseño con los nombres de miembro de un tipo personalizado.For example, you may bind a DataGridView control to an object exposed by a Web service and want the DataGridView control to label its columns at design time with the member names of a custom type.

Puede enlazar fácilmente un control a un tipo con el componente BindingSource.You can easily bind a control to a type with the BindingSource component.

EjemploExample

En el ejemplo de código siguiente se muestra cómo enlazar un control DataGridView a un tipo personalizado mediante un componente BindingSource.The following code example demonstrates how to bind a DataGridView control to a custom type by using a BindingSource component. Al ejecutar el ejemplo, observará que DataGridView ha etiquetado las columnas que reflejan las propiedades de un objeto Customer antes de que el control se rellene con datos.When you run the example, you'll notice the DataGridView has labeled columns that reflect the properties of a Customer object, before the control is populated with data. El ejemplo tiene un botón Add Customer para agregar datos al control DataGridView.The example has an Add Customer button to add data to the DataGridView control. Al hacer clic en el botón, se agrega un nuevo objeto Customer al BindingSource.When you click the button, a new Customer object is added to the BindingSource. En un escenario real, los datos se pueden obtener mediante una llamada a un servicio Web o a otro origen de datos.In a real-world scenario, the data might be obtained by a call to a Web service or other data source.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Windows.Forms;

class Form1 : Form
{
    BindingSource bSource = new BindingSource();
    private Button button1;
    DataGridView dgv = new DataGridView();

    public Form1()
    {
        this.button1 = new System.Windows.Forms.Button();
        this.button1.Location = new System.Drawing.Point(140, 326);
        this.button1.Name = "button1";
        this.button1.AutoSize = true;
        this.button1.Text = "Add Customer";
        this.button1.Click += new System.EventHandler(this.button1_Click);
        this.ClientSize = new System.Drawing.Size(362, 370);
        this.Controls.Add(this.button1);

        // Bind the BindingSource to the DemoCustomer type.
        bSource.DataSource = typeof(DemoCustomer);

        // Set up the DataGridView control.
        dgv.Dock = DockStyle.Top;
        this.Controls.Add(dgv);

        // Bind the DataGridView control to the BindingSource.
        dgv.DataSource = bSource;
       
    }
    public static void Main()
    {
        Application.Run(new Form1());
     
    }

    private void button1_Click(object sender, EventArgs e)
    {
        bSource.Add(new DemoCustomer(DateTime.Today));
    }
}

// This simple class is used to demonstrate binding to a type.
public class DemoCustomer
{
    public DemoCustomer()
    {
        idValue = Guid.NewGuid();
    }

    public DemoCustomer(DateTime FirstOrderDate)
    {
        FirstOrder = FirstOrderDate;
        idValue = Guid.NewGuid();
    }
    // These fields hold the data that backs the public properties.
    private DateTime firstOrderDateValue;
    private Guid idValue;
    private string custNameValue;

    public string CustomerName
    {
        get { return custNameValue; }
        set { custNameValue = value; }
    }
    
    // This is a property that represents a birth date.
    public DateTime FirstOrder
    {
        get
        {
            return this.firstOrderDateValue;
        }
        set
        {
            if (value != this.firstOrderDateValue)
            {
                this.firstOrderDateValue = value;
            }
        }
    }

    // This is a property that represents a customer ID.
    public Guid ID
    {
        get
        {
            return this.idValue;
        }
    }
}
Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Data
Imports System.Drawing
Imports System.Windows.Forms

Class Form1
    Inherits Form
    Private bSource As New BindingSource()
    Private WithEvents button1 As Button
    Private dgv As New DataGridView()

    Public Sub New()
        Me.button1 = New System.Windows.Forms.Button()
        Me.button1.Location = New System.Drawing.Point(140, 326)
        Me.button1.Name = "button1"
        Me.button1.AutoSize = True
        Me.button1.Text = "Add Customer"
        Me.ClientSize = New System.Drawing.Size(362, 370)
        Me.Controls.Add(Me.button1)

        ' Bind the BindingSource to the DemoCustomer type.
        bSource.DataSource = GetType(DemoCustomer)

        ' Set up the DataGridView control.
        dgv.Dock = DockStyle.Top
        Me.Controls.Add(dgv)

        ' Bind the DataGridView control to the BindingSource.
        dgv.DataSource = bSource

    End Sub

    Public Shared Sub Main()
        Application.Run(New Form1())

    End Sub

    Private Sub button1_Click(ByVal sender As Object, ByVal e As EventArgs) _
        Handles button1.Click
        bSource.Add(New DemoCustomer(DateTime.Today))

    End Sub
End Class

' This simple class is used to demonstrate binding to a type.
Public Class DemoCustomer

    Public Sub New()
        idValue = Guid.NewGuid()
    End Sub

    Public Sub New(ByVal FirstOrderDate As DateTime)
        FirstOrder = FirstOrderDate
        idValue = Guid.NewGuid()
    End Sub

    ' These fields hold the data that backs the public properties.
    Private firstOrderDateValue As DateTime
    Private idValue As Guid
    Private custNameValue As String

    Public Property CustomerName() As String
        Get
            Return custNameValue
        End Get
        Set(ByVal value As String)
            custNameValue = value
        End Set
    End Property

    ' This is a property that represents the first order date.
    Public Property FirstOrder() As DateTime
        Get
            Return Me.firstOrderDateValue
        End Get
        Set(ByVal value As DateTime)
            If value <> Me.firstOrderDateValue Then
                Me.firstOrderDateValue = value
            End If
        End Set
    End Property

    ' This is a property that represents a customer ID.
    Public ReadOnly Property ID() As Guid
        Get
            Return Me.idValue
        End Get
    End Property
End Class

Compilar el códigoCompiling the Code

Para este ejemplo se necesita:This example requires:

  • Referencias a los ensamblados System y System.Windows.Forms.References to the System and System.Windows.Forms assemblies.

Vea tambiénSee also