Linguaggio

NotifyParentPropertyAttribute(Boolean) Costruttore

Definizione

Spazio dei nomi:
System.ComponentModel
Assembly:
netstandard.dll, System.ComponentModel.Primitives.dll
Assembly:
System.ComponentModel.Primitives.dll
Assembly:
System.dll
Assembly:
netstandard.dll
Origine:
NotifyParentPropertyAttribute.cs
Origine:
NotifyParentPropertyAttribute.cs
Origine:
NotifyParentPropertyAttribute.cs
Origine:
NotifyParentPropertyAttribute.cs
Origine:
NotifyParentPropertyAttribute.cs

Inizializza una nuova istanza della NotifyParentPropertyAttribute classe utilizzando il valore specificato per determinare se la proprietà padre riceve una notifica delle modifiche apportate al valore della proprietà.

public:
 NotifyParentPropertyAttribute(bool notifyParent);
public NotifyParentPropertyAttribute(bool notifyParent);
new System.ComponentModel.NotifyParentPropertyAttribute : bool -> System.ComponentModel.NotifyParentPropertyAttribute
Public Sub New (notifyParent As Boolean)

Parametri

notifyParent
Boolean

true se l'elemento padre deve ricevere una notifica delle modifiche; in caso contrario, false.

Esempio

Nell'esempio di codice seguente viene illustrato come usare NotifyParentPropertyAttribute e la ExpandableObjectConverter classe per creare una proprietà espandibile in un controllo personalizzato.

[TypeConverter(typeof(BorderAppearanceConverter))]
public class BorderAppearance
{
    int borderSizeValue = 1;
    Color borderColorValue = Color.Empty;

    [Browsable(true),
    NotifyParentProperty(true),
    EditorBrowsable(EditorBrowsableState.Always),
    DefaultValue(1)]
    public int BorderSize
    {
        get => borderSizeValue;
        set
        {
            if (value < 0)
            {
                throw new ArgumentOutOfRangeException(
                    "BorderSize",
                    value,
                    "must be >= 0");
            }

            if (borderSizeValue != value)
            {
                borderSizeValue = value;
            }
        }
    }

    [Browsable(true)]
    [NotifyParentProperty(true)]
    [EditorBrowsable(EditorBrowsableState.Always)]
    [DefaultValue(typeof(Color), "")]
    public Color BorderColor
    {
        get => borderColorValue;
        set
        {
            if (value.Equals(Color.Transparent))
            {
                throw new NotSupportedException("Transparent colors are not supported.");
            }

            if (borderColorValue != value)
            {
                borderColorValue = value;
            }
        }
    }
}

<TypeConverter(GetType(BorderAppearanceConverter))>  _
Public Class BorderAppearance
    Private borderSizeValue As Integer = 1
    Private borderColorValue As Color = Color.Empty
    
    
    <Browsable(True), NotifyParentProperty(True), EditorBrowsable(EditorBrowsableState.Always), DefaultValue(1)>  _
    Public Property BorderSize() As Integer 
        Get
            Return borderSizeValue
        End Get
        Set
            If value < 0 Then
                Throw New ArgumentOutOfRangeException("BorderSize", value, "must be >= 0")
            End If
            
            If borderSizeValue <> value Then
                borderSizeValue = value
            End If
        End Set
    End Property
    
    
    <Browsable(True), NotifyParentProperty(True), EditorBrowsable(EditorBrowsableState.Always), DefaultValue(GetType(Color), "")>  _
    Public Property BorderColor() As Color 
        Get
            Return borderColorValue
        End Get
        Set
            If value.Equals(Color.Transparent) Then
                Throw New NotSupportedException("Transparent colors are not supported.")
            End If
            
            If borderColorValue <> value Then
                borderColorValue = value
            End If
        End Set
    End Property
End Class

Si applica a

Vedi anche