Hello ,
stringValue is used to return" char * and int " values. Below is my code block.
livenessMode = [[@"blink,turnLeft,turnRight" stringValue] UTF8String]
"stringValue" is running on the IOS 14.7 OS phone, I get the following error on the iOS 15.0 beta phone.
** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSTaggedPointerString stringValue]: unrecognized selector sent to instance 0xb82f333406ee1605' terminating with uncaught exception of type NSException
Your code [[@"blink,turnLeft,turnRight" stringValue] UTF8String] causes compile-time error in Xcode 12.5.1 (not beta).
No visible @interface for 'NSString' declares the selector 'stringValue'
So, it would never run on the IOS 14.7. I guess you have simplified the shown code, but that does not help solving your issue.
As the error message is clearly stating, the method stringValue is not defined for NSString.
Unfortunately, some wrong codes might seemingly work in very limited cases. But you should not rely on such codes would always work.