Normalize strings to uppercase

Strings should be normalized to uppercase. A small group of characters, when they are converted to lowercase, cannot make a round trip. To make a round trip means to convert the characters from one locale to another locale that represents character data differently, and then to accurately retrieve the original characters from the converted characters.

An operation normalizes a string to lowercase.

Change operations that convert strings to lowercase so that the strings are converted to uppercase instead. For example, change String.ToLower(CultureInfo.InvariantCulture) to String.ToUpper(CultureInfo.InvariantCulture).

It's safe to suppress a warning when you're not making security decisions based on the result of the normalization (for example, when you're displaying the result in the UI).