Saving all posts to .NET WebService in XML to DB

I am sure this is an easy question however I am not finding the solution. I want to save the XML files posted to my .NET Web Service. I am sure it is just a simple method call when the service is invoked but I am not finding it. I would like to save the full XML posted to the service

Any help would be greatly appreciated. Thank you in advance.

Solution

Thank you for your help however I found what I was looking for at http://msdn.microsoft.com/en-us/library/system.web.services.protocols.soapextension.aspx

To help anyone else that is new to tring to implement this via WebService's I included the steps that I performed to implement it and modifications so I could save it to the db as well as the file system I performed the following steps. If you have any questions please feel free to aks and I will be happy to answer.

Created a code file in my web service project with the code listed in the in the article
Created a few properties to store values to save to the db
```
private string _requestXml;
private DateTime _start;
```

Then I modified the WriteInput method to save values to those variables.

public void WriteInput(SoapMessage message)
{
    //Begin Edit
    oldStream.Position = 0;
    _requestXml = new StreamReader(_oldStream).ReadToEnd();
    _start = DateTime.UtcNow;
    //End Edit
    //Begin Original Code
    oldStream.Position = 0;
    Copy(oldStream, newStream);
    var fs = new FileStream(filename, FileMode.Append, FileAccess.Write);
    var w = new StreamWriter(fs);
    var soapString = (message is SoapServerMessage) ? "SoapRequest" : "SoapResponse";
    w.WriteLine("-----" + soapString + " at " + DateTime.Now);
    w.Flush();
    newStream.Position = 0;
    Copy(newStream, fs);
    w.Close();
    newStream.Position = 0;
}

Then I modified the WriteOutput to

public void WriteOutput(SoapMessage message)
{
    //Begin Edit
    var responseXml = new StreamReader(newStream).ReadToEnd();
    newStream.Position = 0;
    //Start process for saving to DB 
    //"_requestXml" = Original Request Soap Message
    //"responseXml" = Service Returned Response
    //"_start" = Request Start Time
    //message.MethodInfo.Name = I save this so I know what method from     
    //message.Url = I save this so I know the original ASMX that was hit
    //End Edit
    //Begin Original Code
    newStream.Position = 0;
    var fs = new FileStream(filename, FileMode.Append, FileAccess.Write);
    var w = new StreamWriter(fs);
    var soapString = (message is SoapServerMessage) ? "SoapResponse" : "SoapRequest";
    w.WriteLine("-----" + soapString + " at " + DateTime.Now);
    w.Flush();
    Copy(newStream, fs);
    w.Close();
    newStream.Position = 0;
    Copy(newStream, oldStream);
}

Now all that's left is to add the following to your service call and you should be good to go

[WebMethod, NameSpace.OfyourTraceExtesionClass.TraceExtension]
public void WebMethod1()
{
    //DoSomeStuff
}