Create a new instance of class by name (string) using a look up table.

CreateNewInstanceOfClassByNameUsingLookup.cs

// Creates new instance of a class by name (string).
public IClass GetDataSource(string className)
{
  // Should handle case where the className does not exist in dictionary.

  // Lookup table that maps class string names to a constructor action.
  var classDictonary = new Dictionary<string, Func<IClass>>
  {
    { "ClassA", () => new ClassA()},
    { "ClassB", () => new ClassB()},
    { "ClassC", () => new Class()},
  };

  // Create new instance
  return classDictonary[reportName].Invoke();
}