Won’t it be more useful if there was an enum that will be more clear for changing the cell format than newStyle.Number = 8; Like, for example newStyle.Number = FormatType.CurrencyWithRedNegatives; ?
I always have to check your documentation page about it to know what to use
I think you should first test/implement the numbers format in MS Excel manually and know its relative “Custom” formatting. Now use Style.Custom to assign the Custom format string for your requirement. Well, if we add an enumeration for numbers formatting, it will have lots of members (probably hundreds of enum members) as you know there are different Types of Number Formattings e.g Number, Currency, Accounting DateTime, Percentage, Scientific, Text, etc. Moreover, each category may have different set of levels/options. So, we might not address all the categories with their options representing an enumeration.