RegEx

Hello,

I am facing one of those problems that drives you crazy. Something you used to develop but today you don't know why: nothing works.

I want to use RegEx in a PCL. In the beginning, I had a very complex pattern, now I made it very simplified, but it still doesn't work.

var b = Regex.IsMatch("aaa", "[a-z]*");

b is always false. We agree that it should return true ?

It tried another way :
var match = Regex.Match("aaa", "[a-z]*");
match is null.

Please, do you see anything that could help?

Thanks.

Edit : It always returns false on iOS, and true on Android...