Thursday, May 19, 2011

NSNumber numberWithInt example objc

You can create an NSNumber object with integer value by calling NSNumber numberWithInt method. NSNumber is an general container object for any number(integer, float, double...). Note that NSNumber numberWithInt method returns an autoreleased object. Unless the number is retained, it will go away after AutoReleasePool is drained. [NSNumber numberWithInt example]

#import <Foundation/Foundation.h>
int main(int argc, char *argv[])
{
NSAutoreleasePool *pool = [NSAutoreleasePool new];
NSNumber *objNum;
NSInteger n;
// create a NSNumber object with int value 100.
// it returns an autoreleased object. 
//
objNum = [NSNumber numberWithInt:100];
// Get the integer value from NSNumber.
//
n = [objNum integerValue];
NSLog(@"n:%i",n);
objNum = nil;
 
// allocate a number with Double value. not an autoreleased object.
//
objNum = [[NSNumber alloc]initWithDouble:0.7];
NSLog(@"number:%f", [objNum doubleValue]);
[objNum release];
[pool drain];
return 0; 
}