Objective-C中的字符串格式化输出

%@    Objective-C object, printed as the string returned by descriptionWithLocale: if available, or description otherwise. Also works with CFTypeRef objects, returning the result of the CFCopyDescription function.
%%    ‘%’ character
%d, %D, %i    Signed 32-bit integer (int)
%u, %U    Unsigned 32-bit integer (unsigned int)
%hi    Signed 16-bit integer (short)
%hu    Unsigned 16-bit integer (unsigned short)
%qi    Signed 64-bit integer (long long)
%qu    Unsigned 64-bit integer (unsigned long long)
%x    Unsigned 32-bit integer (unsigned int), printed in hexadecimal using the digits 0–9 and lowercase a–f
%X    Unsigned 32-bit integer (unsigned int), printed in hexadecimal using the digits 0–9 and uppercase A–F
%qx    Unsigned 64-bit integer (unsigned long long), printed in hexadecimal using the digits 0–9 and lowercase a–f
%qX    Unsigned 64-bit integer (unsigned long long), printed in hexadecimal using the digits 0–9 and uppercase A–F
%o, %O    Unsigned 32-bit integer (unsigned int), printed in octal
%f    64-bit floating-point number (dole)
%e    64-bit floating-point number (dole), printed in scientific notation using a lowercase e to introd? the exponent
%E    64-bit floating-point number (dole), printed in scientific notation using an uppercase E to introd? the exponent
%g    64-bit floating-point number (dole), printed in the style of %e if the exponent is less than –4 or greater than or eq
l to the precision, in the style of %f otherwise
%G    64-bit floating-point number (dole), printed in the style of %E if the exponent is less than –4 or greater than or eq
l to the precision, in the style of %f otherwise
%c    8-bit unsigned character (unsigned char), printed by NSLog() as an ASCII character, or, if not an ASCII character, in the octal format \\ddd or the Unicode hexadecimal format \\?, where d is a digit
%C    16-bit Unicode character (unichar), printed by NSLog() as an ASCII character, or, if not an ASCII character, in the octal format \\ddd or the Unicode hexadecimal format \\?, where d is a digit
%s    Null-terminated array of 8-bit unsigned characters. %s interprets its input in the system encoding rather than, for example, UTF-8.
%S    Null-terminated array of 16-bit Unicode characters
%p    Void pointer (void *), printed in hexadecimal with the digits 0–9 and lowercase a–f, with a leading 0x
%L    Length modifier specifying that a following a, A, e, E, f, F, g, or G conversion specifier applies to a long dole argument
%a    64-bit floating-point number (dole), printed in scientific notation with a leading 0x and one hexadecimal digit before the decimal point using a lowercase p to introd? the exponent
%A    64-bit floating-point number (dole), printed in scientific notation with a leading 0X and one hexadecimal digit before the decimal point using a uppercase P to introd? the exponent
%F    64-bit floating-point number (dole), printed in decimal notation
%z    Length modifier specifying that a following d, i, o, u, x, or X conversion specifier applies to a size_t or the corresponding signed integer type argument
%t    Length modifier specifying that a following d, i, o, u, x, or X conversion specifier applies to a ptrdiff_t or the corresponding unsigned integer type argument
%j    Length modifier specifying that a following d, i, o, u, x, or X conversion specifier applies to a intmax_t or uintmax_t argument