PropertyInfo.CanRead Propriété
Définition
Important
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Obtient une valeur indiquant si la propriété peut être lue.
public:
abstract property bool CanRead { bool get(); };
public abstract bool CanRead { get; }
member this.CanRead : bool
Public MustOverride ReadOnly Property CanRead As Boolean
Valeur de propriété
true
si la propriété peut être lue ; sinon, false
.
Implémente
Exemples
L’exemple suivant définit deux propriétés. La première propriété est lisible et la CanRead
propriété est true
. La deuxième propriété n’est pas lisible (il n’existe pas d’accesseur get), et la CanRead
propriété est false
.
using namespace System;
using namespace System::Reflection;
// Define one readable property and one not readable.
public ref class Mypropertya
{
private:
String^ caption;
public:
Mypropertya()
: caption( "A Default caption" )
{}
property String^ Caption
{
String^ get()
{
return caption;
}
void set( String^ value )
{
if ( caption != value )
{
caption = value;
}
}
}
};
public ref class Mypropertyb
{
private:
String^ caption;
public:
Mypropertyb()
: caption( "B Default caption" )
{}
property String^ Caption
{
void set( String^ value )
{
if ( caption != value )
{
caption = value;
}
}
}
};
int main()
{
Console::WriteLine( "\nReflection.PropertyInfo" );
// Define two properties.
Mypropertya^ mypropertya = gcnew Mypropertya;
Mypropertyb^ mypropertyb = gcnew Mypropertyb;
Console::Write( "\nMypropertya->Caption = {0}", mypropertya->Caption );
// Mypropertyb.Caption cannot be read, because
// there is no get accessor.
// Get the type and PropertyInfo.
Type^ MyTypea = Type::GetType( "Mypropertya" );
PropertyInfo^ Mypropertyinfoa = MyTypea->GetProperty( "Caption" );
Type^ MyTypeb = Type::GetType( "Mypropertyb" );
PropertyInfo^ Mypropertyinfob = MyTypeb->GetProperty( "Caption" );
// Get and display the CanRead property.
Console::Write( "\nCanRead a - {0}", Mypropertyinfoa->CanRead );
Console::Write( "\nCanRead b - {0}", Mypropertyinfob->CanRead );
return 0;
}
using System;
using System.Reflection;
// Define one readable property and one not readable.
public class Mypropertya
{
private string caption = "A Default caption";
public string Caption
{
get{return caption;}
set {if(caption!=value) {caption = value;}
}
}
}
public class Mypropertyb
{
private string caption = "B Default caption";
public string Caption
{
set{if(caption!=value) {caption = value;}
}
}
}
class Mypropertyinfo
{
public static int Main()
{
Console.WriteLine("\nReflection.PropertyInfo");
// Define two properties.
Mypropertya Mypropertya = new Mypropertya();
Mypropertyb Mypropertyb = new Mypropertyb();
Console.Write("\nMypropertya.Caption = " + Mypropertya.Caption);
// Mypropertyb.Caption cannot be read, because
// there is no get accessor.
// Get the type and PropertyInfo.
Type MyTypea = Type.GetType("Mypropertya");
PropertyInfo Mypropertyinfoa = MyTypea.GetProperty("Caption");
Type MyTypeb = Type.GetType("Mypropertyb");
PropertyInfo Mypropertyinfob = MyTypeb.GetProperty("Caption");
// Get and display the CanRead property.
Console.Write("\nCanRead a - " + Mypropertyinfoa.CanRead);
Console.Write("\nCanRead b - " + Mypropertyinfob.CanRead);
return 0;
}
}
Imports System.Reflection
' Define one readable property and one not readable.
Public Class Mypropertya
Private myCaption As String = "A Default caption"
Public Property Caption() As String
Get
Return myCaption
End Get
Set(ByVal Value As String)
If myCaption <> value Then
myCaption = value
End If
End Set
End Property
End Class
Public Class Mypropertyb
Private myCaption As String = "B Default caption"
Public WriteOnly Property Caption() As String
Set(ByVal Value As String)
If myCaption <> value Then
myCaption = value
End If
End Set
End Property
End Class
Class Mypropertyinfo
Public Shared Function Main() As Integer
Console.WriteLine(ControlChars.CrLf & "Reflection.PropertyInfo")
' Define two properties.
Dim Mypropertya As New Mypropertya()
Dim Mypropertyb As New Mypropertyb()
Console.Write(ControlChars.Cr & "Mypropertya.Caption = " & _
Mypropertya.Caption)
' Mypropertyb.Caption cannot be read because
' there is no get accessor.
' Get the type and PropertyInfo.
Dim MyTypea As Type = Type.GetType("Mypropertya")
Dim Mypropertyinfoa As PropertyInfo = MyTypea.GetProperty("Caption")
Dim MyTypeb As Type = Type.GetType("Mypropertyb")
Dim Mypropertyinfob As PropertyInfo = MyTypeb.GetProperty("Caption")
' Get and display the CanRead property.
Console.Write(ControlChars.CrLf & "CanRead a - " & _
Mypropertyinfoa.CanRead)
Console.Write(ControlChars.CrLf & "CanRead b - " & _
Mypropertyinfob.CanRead)
Return 0
End Function
End Class
Remarques
Si la propriété n’a pas d’accesseur get
, elle ne peut pas être lue.
Pour obtenir la CanRead
propriété, commencez par obtenir la classe Type
. À partir de Type
, obtenez le PropertyInfo
. À partir de , PropertyInfo
obtenez la CanRead
valeur .