KeyPressEventArgs.Handled Proprietà

Definizione

Ottiene o imposta un valore che indica se l'evento KeyPress è stato gestito.Gets or sets a value indicating whether the KeyPress event was handled.

public:
 property bool Handled { bool get(); void set(bool value); };
public bool Handled { get; set; }
member this.Handled : bool with get, set
Public Property Handled As Boolean

Valore della proprietà

true se l'evento è gestito; in caso contrario, false.true if the event is handled; otherwise, false.

Esempi

Nell'esempio seguente viene creato TextBox un controllo.The following example creates a TextBox control. Il keypressed metodo usa la KeyChar proprietà per verificare se è stato premuto il tasto INVIO.The keypressed method uses the KeyChar property to check whether the ENTER key is pressed. Se viene premuto il tasto invio, la Handled proprietà viene impostata su true, che indica che l'evento è gestito.If the ENTER key is pressed, the Handled property is set to true, which indicates the event is handled.

#using <System.dll>
#using <System.Drawing.dll>
#using <System.Windows.Forms.dll>

using namespace System;
using namespace System::Windows::Forms;

public ref class Form1: public Form
{
public:
   Form1()
   {
      // Create a TextBox control.
      TextBox^ tb = gcnew TextBox;
      this->Controls->Add( tb );
      tb->KeyPress += gcnew KeyPressEventHandler( this, &Form1::keypressed );
   }

private:
   void keypressed( Object^ /*o*/, KeyPressEventArgs^ e )
   {
      // The keypressed method uses the KeyChar property to check 
      // whether the ENTER key is pressed. 
      // If the ENTER key is pressed, the Handled property is set to true, 
      // to indicate the event is handled.
      if ( e->KeyChar == (char)13 )
            e->Handled = true;
   }
};

int main()
{
   Application::Run( gcnew Form1 );
}

using System;
using System.Windows.Forms;

public class Form1: Form
{
    public Form1()
    {
        // Create a TextBox control.
        TextBox tb = new TextBox();
        this.Controls.Add(tb);
        tb.KeyPress += new KeyPressEventHandler(keypressed);
    }

    private void keypressed(Object o, KeyPressEventArgs e)
    {
        // The keypressed method uses the KeyChar property to check 
        // whether the ENTER key is pressed. 

        // If the ENTER key is pressed, the Handled property is set to true, 
        // to indicate the event is handled.
        if (e.KeyChar == (char)Keys.Return)
        {
            e.Handled = true;
        }
    }

    public static void Main()
    {
        Application.Run(new Form1());
    }
}
Imports System.Windows.Forms

Public Class Form1
    Inherits Form

    Public Sub New()
        ' Create a TextBox control.
        Dim tb As New TextBox()
        Me.Controls.Add(tb)
        AddHandler tb.KeyPress, AddressOf keypressed
    End Sub

    Private Sub keypressed(ByVal o As [Object], ByVal e As KeyPressEventArgs)
        ' The keypressed method uses the KeyChar property to check 
        ' whether the ENTER key is pressed. 

        ' If the ENTER key is pressed, the Handled property is set to true, 
        ' to indicate the event is handled.

        If e.KeyChar = Microsoft.VisualBasic.ChrW(Keys.Return) Then
            e.Handled = True
        End If
    End Sub

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

Commenti

Se l'evento non è gestito, verrà inviato al sistema operativo per l'elaborazione predefinita.If the event is not handled, it will be sent to the operating system for default processing. Impostare Handled KeyPress su true per annullare l'evento.Set Handled to true to cancel the KeyPress event.

Si applica a

Vedi anche