使用IF或Select Case在Excel UDF中获得更好的性能

I need often to search in Excel with formulas for some special texts in a cell. The number of rows i need to search are 100.000 to 500.000, in rare case up to 1.000.000. To avoid long formulas i wrote a own UDF to search for multiple text strings in a cell. The new formula is short to handle. I optimize the runtime of this formula as good as i can. It needs 11 to 12 sec for 500.000 rows. I need often to search in Excel with formulas f