Object-C 學習筆記(十二)---Foundation之NSNumer

跟其他面相對象語言一樣,OC可以把基本數據類型封裝成爲類,這樣能夠做到更多地事情,擴展性能強.

同時也提供了封裝類還原成爲基本數據類型的方法.

例子:

//
//  main.m
//  Foundation-NSNumber
//
//  Created by 5016 on 13-12-11.
//  Copyright (c) 2013年 dradon. All rights reserved.
//

#import <Foundation/Foundation.h>

int main(int argc, const char * argv[])
{

    @autoreleasepool {
        //NSNumber類把基本數據類型包裝成爲類
//        - (char)charValue;
//        - (unsigned char)unsignedCharValue;
//        - (short)shortValue;
//        - (unsigned short)unsignedShortValue;
//        - (int)intValue;
//        - (unsigned int)unsignedIntValue;
//        - (long)longValue;
//        - (unsigned long)unsignedLongValue;
//        - (long long)longLongValue;
//        - (unsigned long long)unsignedLongLongValue;
//        - (float)floatValue;
//        - (double)doubleValue;
//        - (BOOL)boolValue;
//        - (NSInteger)integerValue NS_AVAILABLE(10_5, 2_0);
//        - (NSUInteger)unsignedIntegerValue NS_AVAILABLE(10_5, 2_0);
        //創建一個NSNumber對象
        NSNumber *mon = [NSNumber numberWithInt:12];
        NSNumber *length = [NSNumber numberWithFloat:1.72];
        NSLog(@"mon=%@ ; length = %@",mon,length);
        
        //還原成爲基本數據類型
//        - (char)charValue;
//        - (unsigned char)unsignedCharValue;
//        - (short)shortValue;
//        - (unsigned short)unsignedShortValue;
//        - (int)intValue;
//        - (unsigned int)unsignedIntValue;
//        - (long)longValue;
//        - (unsigned long)unsignedLongValue;
//        - (long long)longLongValue;
//        - (unsigned long long)unsignedLongLongValue;
//        - (float)floatValue;
//        - (double)doubleValue;
//        - (BOOL)boolValue;
//        - (NSInteger)integerValue NS_AVAILABLE(10_5, 2_0);
//        - (NSUInteger)unsignedIntegerValue NS_AVAILABLE(10_5, 2_0);
//        - (NSString *)stringValue;
        
        int month = [mon intValue];
        float len = [length floatValue];
        NSLog(@"mon=%d ; length = %f",month,len);
        
    }
    return 0;
}