我想问一下 iOS 上 Objective-C 中的基本数据类型。
我需要表示变量的大小和变量的范围。 所以在例子中： short int - 2 个字节 - 有符号：-32768 到 32767 和无符号：0 到 65535 这只是一个例子。
【问题讨论】：
C相同的基本数据类型。
标签： ios objective-c
这是一个很好的概述：
http://reference.jumpingmonkey.org/programming_languages/objective-c/types.html
或运行此代码：
32 位进程：
NSLog(@"Primitive sizes:");
NSLog(@"The size of a char is: %d.", sizeof(char));
NSLog(@"The size of short is: %d.", sizeof(short));
NSLog(@"The size of int is: %d.", sizeof(int));
NSLog(@"The size of long is: %d.", sizeof(long));
NSLog(@"The size of long long is: %d.", sizeof(long long));
NSLog(@"The size of a unsigned char is: %d.", sizeof(unsigned char));
NSLog(@"The size of unsigned short is: %d.", sizeof(unsigned short));
NSLog(@"The size of unsigned int is: %d.", sizeof(unsigned int));
NSLog(@"The size of unsigned long is: %d.", sizeof(unsigned long));
NSLog(@"The size of unsigned long long is: %d.", sizeof(unsigned long long));
NSLog(@"The size of a float is: %d.", sizeof(float));
NSLog(@"The size of a double is %d.", sizeof(double));
NSLog(@"Ranges:");
NSLog(@"CHAR_MIN: %c", CHAR_MIN);
NSLog(@"CHAR_MAX: %c", CHAR_MAX);
NSLog(@"SHRT_MIN: %hi", SHRT_MIN); // signed short int
NSLog(@"SHRT_MAX: %hi", SHRT_MAX);
NSLog(@"INT_MIN: %i", INT_MIN);
NSLog(@"INT_MAX: %i", INT_MAX);
NSLog(@"LONG_MIN: %li", LONG_MIN); // signed long int
NSLog(@"LONG_MAX: %li", LONG_MAX);
NSLog(@"ULONG_MAX: %lu", ULONG_MAX); // unsigned long int
NSLog(@"LLONG_MIN: %lli", LLONG_MIN); // signed long long int
NSLog(@"LLONG_MAX: %lli", LLONG_MAX);
NSLog(@"ULLONG_MAX: %llu", ULLONG_MAX); // unsigned long long int
在 iPhone 3GS 上运行时（iPod Touch 和旧款 iPhone 应该会产生相同的结果），您会得到：
Primitive sizes:
The size of a char is: 1.
The size of short is: 2.
The size of int is: 4.
The size of long is: 4.
The size of long long is: 8.
The size of a unsigned char is: 1.
The size of unsigned short is: 2.
The size of unsigned int is: 4.
The size of unsigned long is: 4.
The size of unsigned long long is: 8.
The size of a float is: 4.
The size of a double is 8.
Ranges:
CHAR_MIN: -128
CHAR_MAX: 127
SHRT_MIN: -32768
SHRT_MAX: 32767
INT_MIN: -2147483648
INT_MAX: 2147483647
LONG_MIN: -2147483648
LONG_MAX: 2147483647
ULONG_MAX: 4294967295
LLONG_MIN: -9223372036854775808
LLONG_MAX: 9223372036854775807
ULLONG_MAX: 18446744073709551615
64位进程：
The size of a char is: 1.
The size of short is: 2.
The size of int is: 4.
The size of long is: 8.
The size of long long is: 8.
The size of a unsigned char is: 1.
The size of unsigned short is: 2.
The size of unsigned int is: 4.
The size of unsigned long is: 8.
The size of unsigned long long is: 8.
The size of a float is: 4.
The size of a double is 8.
Ranges:
CHAR_MIN: -128
CHAR_MAX: 127
SHRT_MIN: -32768
SHRT_MAX: 32767
INT_MIN: -2147483648
INT_MAX: 2147483647
LONG_MIN: -9223372036854775808
LONG_MAX: 9223372036854775807
ULONG_MAX: 18446744073709551615
LLONG_MIN: -9223372036854775808
LLONG_MAX: 9223372036854775807
ULLONG_MAX: 18446744073709551615
【讨论】：
请注意，您也可以在 Objective-C 中完美地使用 C99 固定宽度类型：
#import <stdint.h>
...
int32_t x; // guaranteed to be 32 bits on any platform
如果您没有 C 标准的副本，wikipedia page 可以很好地描述此标头中可用的内容（不过，您应该这样做，因为 Objective-C 只是 C 的一个微小扩展）。您可能还会发现标题 limits.h 和 inttypes.h 很有用。
【讨论】：
新的 64 位架构更新
Ranges:
CHAR_MIN: -128
CHAR_MAX: 127
SHRT_MIN: -32768
SHRT_MAX: 32767
INT_MIN: -2147483648
INT_MAX: 2147483647
LONG_MIN: -9223372036854775808
LONG_MAX: 9223372036854775807
ULONG_MAX: 18446744073709551615
LLONG_MIN: -9223372036854775808
LLONG_MAX: 9223372036854775807
ULLONG_MAX: 18446744073709551615
【讨论】：