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FeatureSupport Class

Definition

Provides static methods for retrieving feature information from the current system.

public ref class FeatureSupport abstract : System::Windows::Forms::IFeatureSupport
public abstract class FeatureSupport : System.Windows.Forms.IFeatureSupport
type FeatureSupport = class
    interface IFeatureSupport
Public MustInherit Class FeatureSupport
Implements IFeatureSupport
Inheritance
FeatureSupport
Derived
Implements

Examples

The following 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 assumes 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

Use the static methods of this class when the classes you query for feature information implement the IFeatureSupport interface. Otherwise, inherit from FeatureSupport and provide your own implementation. For an implementation of this class, see OSFeature.

To get the version number of a feature, call GetVersionPresent. Call IsPresent to determine if a particular feature or version of a feature is installed.

Notes to Implementers

When you inherit from FeatureSupport, you must override the GetVersionPresent(String, String) 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 also must override IsPresent(String, String).

Constructors

FeatureSupport()

Initializes a new instance of the FeatureSupport class.

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
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.

IsPresent(Object, Version)

Determines whether the specified or newer version of the specified feature is installed in the system.

IsPresent(Object)

Determines whether any version of the specified feature is installed in the system.

IsPresent(String, String, Version)

Determines whether the specified or newer version of the specified feature is installed in the system. This method is static.

IsPresent(String, String)

Determines whether any version of the specified feature is installed in the system. This method is static.

MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also