Difference between revisions of "Objective-C"
From Wikicliki
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* bool (true/false) | * bool (true/false) | ||
=== Initialisation === | === Initialisation === | ||
| − | int myInteger; | + | * int myInteger; |
| − | int myInteger = 42; | + | * int myInteger = 42; |
| − | int myInteger, myInteger2, myInteger3; | + | * int myInteger, myInteger2, myInteger3; |
=== Operators === | === Operators === | ||
| − | operators - as normally expected except there is also "modulo" | + | * operators - as normally expected except there is also "modulo" |
| − | % - result will be the remainder from the integer division of the 1st by the 2nd | + | * % - result will be the remainder from the integer division of the 1st by the 2nd |
| − | (only for int or long, insert some caveat here about floats and doubles and using [http://www.cplusplus.com/reference/cmath/fmod/ fmod]) | + | * (only for int or long, insert some caveat here about floats and doubles and using [http://www.cplusplus.com/reference/cmath/fmod/ fmod]) |
| − | eg: int moduloResult = a % b; | + | * eg: int moduloResult = a % b; |
=== NSLog === | === NSLog === | ||
| + | String Formatters for the trace/nslog: | ||
| + | |||
| + | NSLog(@" a %% b = %i", c) | ||
| + | Prints: c = b % a; | ||
| + | |||
| + | <pre>int myNum = 7; | ||
| + | NSString *myString = @"Dog"; | ||
| + | NSLog(@"The number is %i and the string is %@.", myNum, | ||
| + | myString);</pre> | ||
| + | |||
| + | If you want a % sign you have to put in %%. | ||
| + | |||
| + | <pre>NSLog(@"%@", [NSNumber numberWithInt:i]); | ||
| + | |||
| + | %@ Object | ||
| + | %d, %i signed int | ||
| + | %u unsigned int | ||
| + | %f float/double | ||
| + | %1.2f to controll number of decimals | ||
| + | %x, %X hexadecimal int | ||
| + | %o octal int | ||
| + | %zu size_t | ||
| + | %p pointer | ||
| + | %e float/double (in scientific notation) | ||
| + | %g float/double (as %f or %e, depending on value) | ||
| + | %s C string (bytes) | ||
| + | %S C string (unichar) | ||
| + | %.*s Pascal string (requires two arguments, pass pstr[0] as the first, pstr+1 as the second) | ||
| + | %c character | ||
| + | %C unichar | ||
| + | %lld long long | ||
| + | %llu unsigned long long | ||
| + | %Lf long double | ||
| + | </pre> | ||
== See also == | == See also == | ||
Revision as of 09:23, 21 February 2013
Objective-C is a superset of C language and it is called objective-c because it is a object-oriented language.
Contents
What one needs in order to program in Objective-C
- Source Code Editor (Xcode)
- Compiler (Xcode)
- Program to design the interface (Interface Builder - which is now built into Xcode)
- Debuggers (Instruments)
Get Xcode
Basics
Data types in Objective-C
- int (integer)
- unsigned int
- float (floating point number)
- double (double precision)
- char (a, b, c)
- string ("a string")
- bool (true/false)
Initialisation
- int myInteger;
- int myInteger = 42;
- int myInteger, myInteger2, myInteger3;
Operators
- operators - as normally expected except there is also "modulo"
- % - result will be the remainder from the integer division of the 1st by the 2nd
- (only for int or long, insert some caveat here about floats and doubles and using fmod)
- eg: int moduloResult = a % b;
NSLog
String Formatters for the trace/nslog:
NSLog(@" a %% b = %i", c) Prints: c = b % a;
int myNum = 7;
NSString *myString = @"Dog";
NSLog(@"The number is %i and the string is %@.", myNum,
myString);
If you want a % sign you have to put in %%.
NSLog(@"%@", [NSNumber numberWithInt:i]); %@ Object %d, %i signed int %u unsigned int %f float/double %1.2f to controll number of decimals %x, %X hexadecimal int %o octal int %zu size_t %p pointer %e float/double (in scientific notation) %g float/double (as %f or %e, depending on value) %s C string (bytes) %S C string (unichar) %.*s Pascal string (requires two arguments, pass pstr[0] as the first, pstr+1 as the second) %c character %C unichar %lld long long %llu unsigned long long %Lf long double
