Maui IOS String.IndexOf

[galex66]

Hello everyone
If I write this code:
string BufferRX = “HELLO”;
int Pos = BufferRX.IndexOf("E");
Pos is equal 1

but if I write
string BufferRX = “”;
int Pos = BufferRX.IndexOf("E");
Pos is equal -1

That's all Ok

If I put this code in Maui Android or Windows, Pos = -1, but if I put it in IOS Pos = 0

This is a Bug ????
I try with .core 9.0