1. IOS formatted output symbol
%@ Object
%d,%i integer
%u unsigned shaping
%f floating point (double byte)
%x,%x binary integers
%o Eight-binary integers
%zi positive integers
%zu size_t
%p pointer
%e floating point/Double byte (scientific calculation)
%g f floating point/double byte
%s C string
%。 *s Pascal String
%c character
%c Unichar
%LLD 64-bit long integer
%llu unsigned 64-bit long integer
%LF 64-bit double-byte
2. Data type Conversion
2.1. Convert NSString to int
NSString *intstring=@ "123";
int i=[intstring integervalue];
2.2, int convert string
NSString *str=[nsstring stringwithformat:@ "%d", I];
2.3. Convert character to float
float f=[str floatvalue];
2.4. Float converted to string
nsstring *strfloat=[nsstring stringwithformat:@ "%f", f];
Original http://blog.csdn.net/u011872945/article/details/16897619
[GO] IOS formatted output symbol and type conversion