Storing any File Type in a Microsoft Dynamics CRM 2011 Solution as a Web Resource

I ran into a situation the other day where I had to store an oddball file type in a CRM solution that was to be reconstituted and used by code within a plugin from CRM Online.  My thought was to store the file as a web resource but quickly realized that there wasn't a file type for my file.  But I still got it in there.

Here's how:

1. Rename the file extension to .xml and choose the XML file type.  

2. It seems that the application doesn't actually check to see if the file type matches within the file and just blindly uploads it.

3. You can now reconstitute the file from a byte array in code by examining the content attribute of that particular webresource entity.  It is base64 encoded (probably to avoid having to use escape sequences), but that is an easy thing to deal with in .NET.  If I spit the byte array out to a file using a stream reader I can verify that the SHA-1 hash of the reconstituted file matches that of the original file, and it does.

Here is what the code looks like to retrieve your file using C#.  In this example we will spit it out to a file.  This code just uses a retrievemultiple to call to get the webresource, decodes the content attribute into an array of bytes and spits it out to a file.

RetrieveMultipleRequest rmr = new RetrieveMultipleRequest();
      RetrieveMultipleResponse resp = new RetrieveMultipleResponse();
      WebResource wr = new WebResource();

      QueryExpression query = new QueryExpression()
      {
          EntityName = "webresource",
          ColumnSet = new ColumnSet("content"),
          Criteria = new FilterExpression
          {
              FilterOperator = LogicalOperator.And,
              Conditions = 
                {
                    new ConditionExpression
                    {
                        AttributeName = "name",
                        Operator = ConditionOperator.Equal,
                        Values = { "new_testwebresource" }
                    }
                }
          }
      };

      rmr.Query = query;
      resp = (RetrieveMultipleResponse)service.Execute(rmr);
      wr = (WebResource)resp.EntityCollection.Entities[0];
      byte[] filebytes = Convert.FromBase64String(wr.Content);
      FileStream fs = new FileStream(@"c:\testfiles\randomfile.ext",FileMode.Create);
      foreach (byte b in filebytes)
      {
          fs.WriteByte(b);
      }
      fs.Close();

I hope this helps!