Objective-C Numbers/数字

来源：网络整理注：由于水平有限，欢迎指正。转载请务必注明出处。

在Objective-C编程语言，为了保存的基本数据类型，如整型，浮点型，布尔对象的形式，

Objective-C中提供了一系列的NSNumber和重要的工作方法是下表中列出。

S.N.	方法和说明
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.

下面是一个简单的例子，使用的NSNumber两个数字相乘，并返回该产品。

#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;
}

现在，当我们编译并运行程序，我们会得到以下的结果。

2013-09-14 18:53:40.575 demo[16787] The product is 105

本站文章除注明转载外，均为本站原创或编译
欢迎任何形式的转载，但请务必注明出处，尊重他人劳动共创优秀实例教程
转载请注明：文章转载自：代码驿站 [http:/www.codeinn.net]
本文标题：Objective-C Numbers/数字
本文地址：http://www.codeinn.net/oc/584.html