Providers that currently ignore duplicates should continue to do so to avoid breaking existing apps
For 3.0 we would consider a change that consolidated all the exception types/messages across providers into one consistent exception and message. (This is technically also a breaking change, but one that is unlikely to cause real-world issues. Still; better to do it in 3.0 than in a non-breaking release.)
See https://github.com/aspnet/Extensions/pull/600
Specifically, duplicates within a given source. For example, the same setting repeated twice in an
.ini
file.These providers throw either
ArgumentException
orFormatException
:These providers ignore duplicates if the case does match:
These providers ignore duplicates if the case does not match:
These providers ignore duplicates: