SSRS: How can I accessing report parameters from custom assembly?

reporting-services, ssrs-2008

Solution

I don't think you can. The corresponding MSDN documentation mentions that you can use parameters in custom assemblies:

You can reference the global parameters collection via custom code in a Code block of the report definition or in a custom assembly that you provide. The parameters collection is read-only and has no public iterators.

But the examples provided both require you to provide all parameters or just one as an argument to the custom code functions, e.g.

' Passing an entire global parameter collection to custom code.
' This function returns the value of a specific report parameter MyParameter.
Public Function DisplayAParameterValue(ByVal parameters as Parameters) as Object
    Return parameters("MyParameter").Value
End Function

And:

' Passing an individual parameter to custom code.
' This example returns the value of the parameter
' passed in. If the parameter is a multivalue parameter, 
' the return string is a concatenation of all the values.
Public Function ShowParameterValues(ByVal parameter as Parameter)
 as String
   Dim s as String 
   If parameter.IsMultiValue then
      s = "Multivalue: " 
      For i as integer = 0 to parameter.Count-1
         s = s + CStr(parameter.Value(i)) + " " 
      Next
   Else
      s = "Single value: " + CStr(parameter.Value)
   End If
   Return s
End Function

Problem

Original source