如何：在配置 SOAP 扩展时初始化缓存数据
本主题专门介绍一项旧有技术。现在应通过使用以下链接来创建 XML Web 服务和 XML Web 服务客户端： Windows Communication Foundation.
下面的代码示例根据 SOAP 扩展的最终配置方式初始化 GetInitializer 方法中的一段缓存数据。如果使用特性（在此示例中为 TraceExtensionAttribute）配置 SOAP 扩展，则会缓存该特性中指定的文件名。如果 SOAP 扩展是使用配置文件配置的，则会根据 Web 服务的类型来计算缓存的文件名。
示例
' When the SOAP extension is accessed for the first time, the XML
' Web service method it is applied to is accessed to store the file
' name passed in, using the corresponding SoapExtensionAttribute.
Public Overloads Overrides Function GetInitializer(methodInfo As _
LogicalMethodInfo, attribute As SoapExtensionAttribute) As Object
Return CType(attribute, TraceExtensionAttribute).Filename
End Function
' The extension was configured to run using a configuration file
' instead of an attribute applied to a specific Web service method.
' Return a file name, based on the class implementing the XML Web
' service's type.
Public Overloads Overrides Function GetInitializer(WebServiceType As _
Type) As Object
' Return a file name to log the trace information, based on the type.
Return "C:\" + WebServiceType.FullName + ".log"
End Function
// When the SOAP extension is accessed for the first time, the XML
// Web service method it is applied to is accessed to store the file
// name passed in, using the corresponding SoapExtensionAttribute.
public override object GetInitializer(LogicalMethodInfo methodInfo,
SoapExtensionAttribute attribute)
{
return ((TraceExtensionAttribute) attribute).Filename;
}
// The extension was configured to run using a configuration file instead of
// an attribute applied to a specific Web service method.
public override object GetInitializer(Type WebServiceType)
{
// Return a file name to log the trace information, based on the type.
return "C:\\" + WebServiceType.FullName + ".log";}