方法的元标记如何工作​​？

Question

我有这个元SoapHeader，SoapDocumentMethod ...我怎么知道它们何时被执行？，在执行方法之前或执行之后？这个元数据执行的方法在哪里？它有什么名字？

[SoapHeader("AgentInfoHeaderValue")]
[SoapDocumentMethod("http://www.example.com/xml/andromeda#WORK", RequestNamespace = "http://www.example.com/xml/someapi", ResponseNamespace = "http://www.example.com/xml/someapi", 
    Use = System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle = SoapParameterStyle.Wrapped)]
[return: XmlElement("return", Namespace = "", IsNullable = false, DataType = "base64Binary")]
public byte[] WORK([XmlElement(Namespace = "http://www.example.com/xml/someapi", DataType = "string", Form = XmlSchemaForm.Qualified)] string guid, [XmlElement(Namespace = "http://www.example.com/xml/someapi", DataType = "base64Binary", Form = XmlSchemaForm.Qualified)] byte[] data)
{
   //some actions
}