IFeatureSupport.IsPresent Methode

Referenz

Definition

Namespace:: System.Windows.Forms

Assembly:: System.Windows.Forms.dll

Wichtig

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Bestimmt, ob das angegebene Feature derzeit im System verfügbar ist.

Überlädt

IsPresent(Object)	Bestimmt, ob eine beliebige Version des angegebenen Features derzeit im System verfügbar ist.
IsPresent(Object, Version)	Bestimmt, ob die angegebene oder eine neuere Version des angegebenen Features derzeit im System verfügbar ist.

IsPresent(Object)

Bestimmt, ob eine beliebige Version des angegebenen Features derzeit im System verfügbar ist.

public:
 bool IsPresent(System::Object ^ feature);

public bool IsPresent (object feature);

abstract member IsPresent : obj -> bool

Public Function IsPresent (feature As Object) As Boolean

Parameter

feature: Object

Das zu suchende Feature.

Gibt zurück

Boolean

true, wenn das Feature vorhanden ist, andernfalls false.

Beispiele

Im folgenden Beispiel wird die OSFeature Implementierung von IFeatureSupport - und -Abfragen für das LayeredWindows Feature verwendet. Die Version wird überprüft, um festzustellen, ob es sich nullum handelt, um zu bestimmen, ob das Feature vorhanden ist. Das Ergebnis wird in einem Textfeld angezeigt. Dieser Code geht davon aus, dass textBox1 erstellt und auf einem Formular platziert wurde.

private:
   void LayeredWindows()
   {
      // Gets the version of the layered windows feature.
      Version^ myVersion = OSFeature::Feature->GetVersionPresent(
         OSFeature::LayeredWindows );
      
      // Prints whether the feature is available.
      if ( myVersion != nullptr )
      {
         textBox1->Text = "Layered windows feature is installed.\n";
      }
      else
      {
         textBox1->Text = "Layered windows feature is not installed.\n";
      }

      
      // This is an alternate way to check whether a feature is present.
      if ( OSFeature::Feature->IsPresent( OSFeature::LayeredWindows ) )
      {
         textBox1->Text = String::Concat( textBox1->Text,
            "Again, layered windows feature is installed." );
      }
      else
      {
         textBox1->Text = String::Concat( textBox1->Text,
            "Again, layered windows feature is not installed." );
      }
   }

private void LayeredWindows() {
   // Gets the version of the layered windows feature.
   Version myVersion = OSFeature.Feature.GetVersionPresent(OSFeature.LayeredWindows);

   // Prints whether the feature is available.
   if (myVersion != null)
      textBox1.Text = "Layered windows feature is installed." + '\n';
   else
      textBox1.Text = "Layered windows feature is not installed." + '\n';

   // This is an alternate way to check whether a feature is present.
   if (OSFeature.Feature.IsPresent(OSFeature.LayeredWindows))
      textBox1.Text += "Again, layered windows feature is installed.";
   else
      textBox1.Text += "Again, layered windows feature is not installed.";
}

Private Sub LayeredWindows()
    ' Gets the version of the layered windows feature.
    Dim myVersion As Version = _
       OSFeature.Feature.GetVersionPresent(OSFeature.LayeredWindows)
       
    ' Prints whether the feature is available.
    If (myVersion IsNot Nothing) Then
        textBox1.Text = "Layered windows feature is installed." & _
           ControlChars.CrLf
    Else
        textBox1.Text = "Layered windows feature is not installed." & _
           ControlChars.CrLf
    End If 
    'This is an alternate way to check whether a feature is present.
    If OSFeature.Feature.IsPresent(OSFeature.LayeredWindows) Then
        textBox1.Text &= "Again, layered windows feature is installed."
    Else
        textBox1.Text &= "Again, layered windows feature is not installed."
    End If
End Sub

Weitere Informationen

Gilt für:

IsPresent(Object, Version)

Bestimmt, ob die angegebene oder eine neuere Version des angegebenen Features derzeit im System verfügbar ist.

public:
 bool IsPresent(System::Object ^ feature, Version ^ minimumVersion);

public bool IsPresent (object feature, Version minimumVersion);

abstract member IsPresent : obj * Version -> bool

Public Function IsPresent (feature As Object, minimumVersion As Version) As Boolean

Parameter

feature: Object

Das zu suchende Feature.

minimumVersion: Version

Version stellt die kleinstmögliche Versionsnummer des zu suchenden Features dar.

Gibt zurück

Boolean

true, wenn die angeforderte Version des Features vorhanden ist, andernfalls false.

Beispiele

private:
   void LayeredWindows()
   {
      // Gets the version of the layered windows feature.
      Version^ myVersion = OSFeature::Feature->GetVersionPresent(
         OSFeature::LayeredWindows );
      
      // Prints whether the feature is available.
      if ( myVersion != nullptr )
      {
         textBox1->Text = "Layered windows feature is installed.\n";
      }
      else
      {
         textBox1->Text = "Layered windows feature is not installed.\n";
      }

      
      // This is an alternate way to check whether a feature is present.
      if ( OSFeature::Feature->IsPresent( OSFeature::LayeredWindows ) )
      {
         textBox1->Text = String::Concat( textBox1->Text,
            "Again, layered windows feature is installed." );
      }
      else
      {
         textBox1->Text = String::Concat( textBox1->Text,
            "Again, layered windows feature is not installed." );
      }
   }

private void LayeredWindows() {
   // Gets the version of the layered windows feature.
   Version myVersion = OSFeature.Feature.GetVersionPresent(OSFeature.LayeredWindows);

   // Prints whether the feature is available.
   if (myVersion != null)
      textBox1.Text = "Layered windows feature is installed." + '\n';
   else
      textBox1.Text = "Layered windows feature is not installed." + '\n';

   // This is an alternate way to check whether a feature is present.
   if (OSFeature.Feature.IsPresent(OSFeature.LayeredWindows))
      textBox1.Text += "Again, layered windows feature is installed.";
   else
      textBox1.Text += "Again, layered windows feature is not installed.";
}

Private Sub LayeredWindows()
    ' Gets the version of the layered windows feature.
    Dim myVersion As Version = _
       OSFeature.Feature.GetVersionPresent(OSFeature.LayeredWindows)
       
    ' Prints whether the feature is available.
    If (myVersion IsNot Nothing) Then
        textBox1.Text = "Layered windows feature is installed." & _
           ControlChars.CrLf
    Else
        textBox1.Text = "Layered windows feature is not installed." & _
           ControlChars.CrLf
    End If 
    'This is an alternate way to check whether a feature is present.
    If OSFeature.Feature.IsPresent(OSFeature.LayeredWindows) Then
        textBox1.Text &= "Again, layered windows feature is installed."
    Else
        textBox1.Text &= "Again, layered windows feature is not installed."
    End If
End Sub

Weitere Informationen

Gilt für:

Freigeben über

IFeatureSupport.IsPresent Methode

Definition

Überlädt

IsPresent(Object)

Parameter

Gibt zurück

Beispiele

Weitere Informationen

Gilt für:

IsPresent(Object, Version)

Parameter

Gibt zurück

Beispiele

Weitere Informationen

Gilt für:

Zusätzliche Ressourcen