C# variable defined then redefined issue

Question

Hey all I have a question that may or may not have the answer I am looking for.

I want to set the variable _data to something generic so that I can set it again with the proper class name in an if statement.

Example is:

public static void whichStatus(string dataName, object data, sessionVars sVars)
{
   if (dataName == "SAVE_PNo_tTrip")
   {
       object _data; //This is where I attempt to set the variable generic
       var pageName = data.GetType().DeclaringType.Name;

       if (pageName == "CAttend")
       {
            CAttend.SAVE_PNo_tTrip _data = (CAttend.SAVE_PNo_tTrip)data;
            //This is where I need to actually define the real data type for _data.
       }
       etc...etc...
   }

   switch (sVars.userCategory.ToUpper())
   {
       case "CCLASS":
           //_data.ID;
           break;
       case "LNC":
           //_data.ID;
           //_data.Name;
           break;
       etc.. etc...
   }

 

As you see from the above, I am trying to just set _data to something so that I actually define it in the if statement below it. I'll also need to access it from other places within that function so that's why I need to define it at the beginning. Though I am getting an error:

Error CS0136 A local or parameter named '_data' cannot be declared in this scope because that name is used in an enclosing local scope to define a local or parameter

Is it at all possible to do this the way I am trying to do it?