xslTransform.Transform to XslCompiledTransform.Transform

Hi I am clearing all warnings in my application, I used below code in my application

  DataSet dsBillItem = new DataSet();
  System.Xml.XPath.XPathNavigator xNav = xmlResponse.CreateNavigator();
  XslTransform xslTransform = new XslTransform();
  xslTransform.Load("test.xslt");
  XmlReader xmlReader = xslTransform.Transform(xNav, null);
  dsBillItem.ReadXml(xmlReader);

Its showing "XslTransform" showing warning "This class has been deprecated. Please use System.Xml.Xsl.XslCompiledTransform instead. http://ift.tt/1qIVb8r".

If I change my code based on "XslCompiledTransform", its throwing error in this line "XmlReader xmlReader = xslTransform.Transform(xNav, null);". Because this method available with void return type.

Please help me anyone on this, any code for xslt file to dataset conversion or any other way is available?