我认为最简洁的方法可能是以下

I think the cleanest way is probably the following

Array.IndexOf(Parameters!p_myMultipleValueParameter.Value, Fields!groepType.Value) > -1

由于分配额外字符串的开销，每次运行连接可能效率低下，特别是如果函数将在一个大列表上运行，或者每行一次网格，例如.

Running a join each time may be inefficient because of the overhead of allocating extra strings, especially if the function will be run over a large list, or once per row of a grid, say.