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Objective-C - Numbers
Objective-C Numbers
In Objective-C programming language, in order to save the basic data types pke int, float, bool in object form,
Objective-C provides a range of methods to work with NSNumber and important ones are psted in following table.
| Sr.No. | Method & Description |
|---|---|
| 1 | + (NSNumber *)numberWithBool:(BOOL)value Creates and returns an NSNumber object containing a given value, treating it as a BOOL. |
| 2 | + (NSNumber *)numberWithChar:(char)value Creates and returns an NSNumber object containing a given value, treating it as a signed char. |
| 3 | + (NSNumber *)numberWithDouble:(double)value Creates and returns an NSNumber object containing a given value, treating it as a double. |
| 4 | + (NSNumber *)numberWithFloat:(float)value Creates and returns an NSNumber object containing a given value, treating it as a float. |
| 5 | + (NSNumber *)numberWithInt:(int)value Creates and returns an NSNumber object containing a given value, treating it as a signed int. |
| 6 | + (NSNumber *)numberWithInteger:(NSInteger)value Creates and returns an NSNumber object containing a given value, treating it as an NSInteger. |
| 7 | - (BOOL)boolValue Returns the receiver s value as a BOOL. |
| 8 | - (char)charValue Returns the receiver s value as a char. |
| 9 | - (double)doubleValue Returns the receiver s value as a double. |
| 10 | - (float)floatValue Returns the receiver s value as a float. |
| 11 | - (NSInteger)integerValue Returns the receiver s value as an NSInteger. |
| 12 | - (int)intValue Returns the receiver s value as an int. |
| 13 | - (NSString *)stringValue Returns the receiver s value as a human-readable string. |
Here is a simple example for using NSNumber which multippes two numbers and returns the product.
#import <Foundation/Foundation.h>
@interface SampleClass:NSObject
- (NSNumber *)multiplyA:(NSNumber *)a withB:(NSNumber *)b;
@end
@implementation SampleClass
- (NSNumber *)multiplyA:(NSNumber *)a withB:(NSNumber *)b {
float number1 = [a floatValue];
float number2 = [b floatValue];
float product = number1 * number2;
NSNumber *result = [NSNumber numberWithFloat:product];
return result;
}
@end
int main() {
NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
SampleClass *sampleClass = [[SampleClass alloc]init];
NSNumber *a = [NSNumber numberWithFloat:10.5];
NSNumber *b = [NSNumber numberWithFloat:10.0];
NSNumber *result = [sampleClass multiplyA:a withB:b];
NSString *resultString = [result stringValue];
NSLog(@"The product is %@",resultString);
[pool drain];
return 0;
}
Now when we compile and run the program, we will get the following result.
2013-09-14 18:53:40.575 demo[16787] The product is 105Advertisements