FeatureSupport::IsPresent Method (Object^)

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

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public:
virtual bool IsPresent(
	Object^ feature
)

Parameters

feature
Type: System::Object^

The feature to look for.

Return Value

Type: System::Boolean

true if the feature is present; otherwise, false.

Notes to Inheritors:

When you inherit from FeatureSupport, you must override the GetVersionPresent 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 method. If the two feature parameters differ, you must also override IsPresent.

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." );
      }
   }

.NET Framework
Available since 1.1
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