IFeatureSupport.GetVersionPresent(Object) 方法

定义

检索指定功能的版本。Retrieves the version of the specified feature.

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

参数

feature
Object

所要求版本的功能。The feature whose version is requested.

返回

表示指定功能的版本号的 Version;如果该功能未安装,则为 nullA Version representing the version number of the specified feature; or null if the feature is not installed.

示例

下面的示例使用OSFeature IFeatureSupport和查询来实现该LayeredWindows功能。The following example uses the OSFeature implementation of IFeatureSupport and queries for the LayeredWindows feature. 检查版本是否为null, 以确定该功能是否存在。The version is checked to see if it is null, to determine whether the feature is present. 结果将显示在文本框中。The result is displayed in a text box. 此代码假定textBox1已创建并放置在窗体上。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

注解

有关此方法的实现, 请参见GetVersionPresentFor an implementation of this method, see GetVersionPresent.

适用于

另请参阅