Control.EnabledChanged Evento

Definizione

Si verifica quando viene modificato il valore della proprietà Enabled.

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

Tipo evento

Esempio

Nell'esempio di codice seguente vengono utilizzati due RadioButton controlli per illustrare l'evento EnabledChanged . Facendo clic su un pulsante viene modificato il valore della Enabled proprietà dell'altro pulsante false e viene visualizzato un oggetto 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.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 la Enabled proprietà viene modificata da una modifica a livello di codice o da un'interazione dell'utente.

Per ulteriori informazioni sulla gestione degli eventi, consultare gestione e generazione di eventi.

Si applica a

Vedi anche