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FeatureSupport.IsPresent Method (Object)

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)

'Declaration
Public Overridable Function IsPresent ( _
	feature As Object _
) As Boolean

Parameters

feature
Type: System.Object

The feature to look for.

Return Value

Type: System.Boolean
true if the feature is present; otherwise, false.

Implements

IFeatureSupport.IsPresent(Object)

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 Nothing, 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 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

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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