Control.EnabledChanged Control.EnabledChanged Control.EnabledChanged Control.EnabledChanged Event

Definizione

Si verifica quando viene modificato il valore della proprietà Enabled.Occurs when the Enabled property value has changed.

public:
 event EventHandler ^ EnabledChanged;
public event EventHandler EnabledChanged;
member this.EnabledChanged : EventHandler 
Public Custom Event EnabledChanged As EventHandler 

Esempi

L'esempio di codice seguente usa due RadioButton controlli per illustrare il EnabledChanged evento.The following code example uses two RadioButton controls to demonstrate the EnabledChanged event. Facendo clic su un pulsante Modifica il valore della Enabled proprietà del pulsante su false e visualizza un MessageBox.Clicking one button changes the value of the Enabled property of the other button to false and displays a MessageBox.

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

public class Form1 : Form
{
    private RadioButton radioButton1;
    private RadioButton radioButton2;

    public Form1()
    {
        InitializeComponent();
    }
    [STAThread]
    static void Main()
    {
        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        Application.Run(new Form1());
    }

    private void InitializeComponent()
    {
        this.radioButton1 = new System.Windows.Forms.RadioButton();
        this.radioButton2 = new System.Windows.Forms.RadioButton();
        this.SuspendLayout();
        // 
        // radioButton1
        // 
        this.radioButton1.AutoSize = true;
        this.radioButton1.Location = new System.Drawing.Point(0, 0);
        this.radioButton1.Name = "radioButton1";
        this.radioButton1.Size = new System.Drawing.Size(62, 17);
        this.radioButton1.TabIndex = 0;
        this.radioButton1.TabStop = true;
        this.radioButton1.Text = "Button1";
        this.radioButton1.UseVisualStyleBackColor = true;
        this.radioButton1.EnabledChanged += new System.EventHandler(this.radioButton1_EnabledChanged);
        // 
        // radioButton2
        // 
        this.radioButton2.AutoSize = true;
        this.radioButton2.Location = new System.Drawing.Point(0, 39);
        this.radioButton2.Name = "radioButton2";
        this.radioButton2.Size = new System.Drawing.Size(100, 17);
        this.radioButton2.TabIndex = 1;
        this.radioButton2.TabStop = true;
        this.radioButton2.Text = "Disable Button1";
        this.radioButton2.UseVisualStyleBackColor = true;
        this.radioButton2.CheckedChanged += new System.EventHandler(this.radioButton2_CheckedChanged);
        // 
        // Form1
        // 
        this.ClientSize = new System.Drawing.Size(292, 273);
        this.Controls.Add(this.radioButton2);
        this.Controls.Add(this.radioButton1);
        this.Name = "Form1";
        this.ResumeLayout(false);
        this.PerformLayout();

    }

    private void radioButton2_CheckedChanged(object sender, EventArgs e)
    {
        radioButton1.Enabled = false;
    }

    private void radioButton1_EnabledChanged(object sender, EventArgs e)
    {
        MessageBox.Show("This button has been disabled.");
    }
}
Imports System
Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Data
Imports System.Drawing
Imports System.Text
Imports System.Windows.Forms



Public Class Form1
   Inherits Form
   Private WithEvents radioButton1 As RadioButton
   Private WithEvents radioButton2 As RadioButton
   
   
   Public Sub New()
      InitializeComponent()
   End Sub
   
   <STAThread()>  _
   Shared Sub Main()
      Application.EnableVisualStyles()
      Application.SetCompatibleTextRenderingDefault(False)
      Application.Run(New Form1())
   End Sub
   
   
   Private Sub InitializeComponent()
      Me.radioButton1 = New System.Windows.Forms.RadioButton()
      Me.radioButton2 = New System.Windows.Forms.RadioButton()
      Me.SuspendLayout()
      ' 
      ' radioButton1
      ' 
      Me.radioButton1.AutoSize = True
      Me.radioButton1.Location = New System.Drawing.Point(0, 0)
      Me.radioButton1.Name = "radioButton1"
      Me.radioButton1.Size = New System.Drawing.Size(62, 17)
      Me.radioButton1.TabIndex = 0
      Me.radioButton1.TabStop = True
      Me.radioButton1.Text = "Button1"
      Me.radioButton1.UseVisualStyleBackColor = True
      ' 
      ' radioButton2
      ' 
      Me.radioButton2.AutoSize = True
      Me.radioButton2.Location = New System.Drawing.Point(0, 39)
      Me.radioButton2.Name = "radioButton2"
      Me.radioButton2.Size = New System.Drawing.Size(100, 17)
      Me.radioButton2.TabIndex = 1
      Me.radioButton2.TabStop = True
      Me.radioButton2.Text = "Disable Button1"
      Me.radioButton2.UseVisualStyleBackColor = True
      ' 
      ' Form1
      ' 
      Me.ClientSize = New System.Drawing.Size(292, 273)
      Me.Controls.Add(radioButton2)
      Me.Controls.Add(radioButton1)
      Me.Name = "Form1"
      Me.ResumeLayout(False)
      Me.PerformLayout()
   End Sub
    
   
   Private Sub radioButton2_CheckedChanged(sender As Object, e As EventArgs) Handles radioButton2.CheckedChanged
      radioButton1.Enabled = False
   End Sub
   
   
   Private Sub radioButton1_EnabledChanged(sender As Object, e As EventArgs) Handles radioButton1.EnabledChanged
      MessageBox.Show("This button has been disabled.")
   End Sub
End Class

Commenti

Questo evento viene generato se il Enabled proprietà viene modificata da una modifica a livello di codice o l'interazione dell'utente.This event is raised if the Enabled property is changed by either a programmatic modification or user interaction.

Per ulteriori informazioni sulla gestione degli eventi, consultare gestione e generazione di eventi.For more information about handling events, see Handling and Raising Events.

Si applica a

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