How to use a variable value set from custom dll in dataset

Question

Hi,
I've inherited a SSRS report that I need to add some functionality to.  I'm setting a variable, ADAuthorizations, from a custom dll 
ADAuthorizations is a string of all AD groups a user is a member of and I need to use this as a filter in a dataset.  I've tried using this variable as shown in the query below but I'm getting an error "The expression used for the parameter 'Unit_Permissions"
in the dataset "Unit_Permissions" includes a variable reference.  Variable values cannot be used in query parameter expressions."  Is there another way I should go about doing this?   
= "SELECT UnitCode, UnitName " &
  "FROM dbo.VW_Unit_Permissions " &
  "WHERE UserId in (" & Variables!ADAuthorizations.Value & ")" &
  "ORDER BY UnitName "
Thanks,
Robert

Answer 1

Please follow below steps,
1. Create a custom code to get all the users in an array,
Public Function getUserName() As String()
   dim Users(1) as string
   Users(0) = "user1"
   Users(1) = "user2"
return Users
End Function
2. Create dataset using the below query,
SELECT UnitCode, UnitName FROM dbo.VW_Unit_Permissions ORDER BY UnitName
3. Add a parameter @User and set properties : (Datatype as text, Allow multiple values, Visible)
Under "Available Values" select specify values and set the label and values as expression.
=Code.getUserName()
4. Similarly for "Default values" as
=Code.getUserName()
5. Go to tablix properties and select the filter tab and set the properties as below,
- Select Expression "UserId" i.e =Fields!UserId.Value
- Operator as "IN"
- Value as =Parameters!User.Value
6. Preview the report.
Regards, RSingh