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FeatureSupport.GetVersionPresent Method

Definition

Gets the version of the specified feature that is available on the system.

Overloads

GetVersionPresent(Object)

When overridden in a derived class, gets the version of the specified feature that is available on the system.

GetVersionPresent(String, String)

Gets the version of the specified feature that is available on the system.

GetVersionPresent(Object)

When overridden in a derived class, gets the version of the specified feature that is available on the system.

public:
 abstract Version ^ GetVersionPresent(System::Object ^ feature);
public abstract Version GetVersionPresent (object feature);
public abstract Version? GetVersionPresent (object feature);
abstract member GetVersionPresent : obj -> Version
Public MustOverride Function GetVersionPresent (feature As Object) As Version

Parameters

feature
Object

The feature whose version is requested.

Returns

A Version representing the version number of the specified feature available on the system; or null if the feature is not installed.

Implements

Examples

The following code example uses the OSFeature implementation of FeatureSupport and queries for the LayeredWindows feature. The version is checked to see if it is null, to determine whether the feature is present. The result is displayed in a text box. This code requires that textBox1 has been created and placed on a form.

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

Remarks

Version numbers consist of three parts: major, minor, and build. Typically, a version number is displayed as "major number.minor number.build number".

Notes to Implementers

When you inherit from FeatureSupport, you must override this method. When you override this method, check that the class that you use for the feature parameter is the same as the class used for this parameter in the IsPresent(String, String) method. If the two feature parameters differ, you must also override IsPresent(String, String).

See GetVersionPresent(Object) for an implementation of this method.

See also

Applies to

GetVersionPresent(String, String)

Gets the version of the specified feature that is available on the system.

public:
 static Version ^ GetVersionPresent(System::String ^ featureClassName, System::String ^ featureConstName);
public static Version GetVersionPresent (string featureClassName, string featureConstName);
public static Version? GetVersionPresent (string featureClassName, string featureConstName);
static member GetVersionPresent : string * string -> Version
Public Shared Function GetVersionPresent (featureClassName As String, featureConstName As String) As Version

Parameters

featureClassName
String

The fully qualified name of the class to query for information about the specified feature. This class must implement the IFeatureSupport interface or inherit from a class that implements this interface.

featureConstName
String

The fully qualified name of the feature to look for.

Returns

A Version with the version number of the specified feature available on the system; or null if the feature is not installed.

Remarks

Version numbers consist of three parts: major, minor, and build. Typically, a version number is displayed as "major number.minor number.build number".

See the documentation for the product containing the feature to determine the names to pass to the featureClassName and the featureConstName parameters.

See also

Applies to