NSInteger是一个32位整数

Question

Am I correct in thinking that declaring a NSInteger in an ios environment means it will only ever be a 32bit value?

I would like to know as I have been told by another programmer not familiar with objective c to use a int32, the only similar thing I can find in objective C is the int32_t, _t standing for 'integer type'.. but working with these types is becoming a real pain I feel like I dont have all the control functionally thats offered from objective c like NSInteger seems to get.

Any help would be greatly appreciated.

Answer 1

Here is how " NSInteger " is defined in " NSObjCRuntime.h " in older SDK's:

#if __LP64__ || (TARGET_OS_EMBEDDED && !TARGET_OS_IPHONE) || TARGET_OS_WIN32 || NS_BUILD_32_LIKE_64
typedef long NSInteger;
typedef unsigned long NSUInteger;
#else
typedef int NSInteger;
typedef unsigned int NSUInteger;
#endif

As of September 2013, iPhones now can run with 64-bit chips, which means a NSInteger might be much bigger.

In my own coding, if I'm doing pure Objective C, I'll stick with NSInteger since that future-proofs my code for down the line. Open source stuff and certain programmers, on the other hand, love to use " uint32_t " or " int32_t " and other explicit types like this, so when I see those, I try to match their style in the code I'm doing that works with it.

Answer 2

typedef的存在是为了保护你免受基类型的影响，这就是为什么你使用它们而不是原始类型它的被称为可移植性。

Answer 3

Update iOS 11: NSInteger can be 32-bit or 64-bit depending on the application built and the iOS version.

When building 32-bit applications, NSInteger is a 32-bit integer. A 64-bit application treats NSInteger as a 64-bit integer.

https://developer.apple.com/documentation/objectivec/nsinteger