NSNumber 对象

//
//  main.m
//  NSNumber

#import <Foundation/Foundation.h>

int main(int argc, const char * argv[]) {
    @autoreleasepool {
    //NSNumber 数字
        //提供NSNumber类型和基本类型之间的相互转换
        // int float double char Bool signed unsigned
        //基本类型转成NSNumber
        //NSNumberxxx
        int i = 100;
        float f = 3.14;
        BOOL b = YES;
        char c = ‘A‘;
        unsigned int ui = 1000;
        //对象加*号
        NSNumber *num = [NSNumber numberWithInt:i];
        NSNumber *num1 = [NSNumber numberWithFloat:f];
        NSNumber *num2 = [NSNumber numberWithBool:b];
        NSNumber *num3 = [NSNumber numberWithChar:c];
        NSNumber *num4 = [NSNumber numberWithUnsignedInt:ui];
        
        
        NSUInteger x = 100;
        NSNumber *num5 = [NSNumber numberWithUnsignedInteger:x];
        NSInteger y = 200;
        NSNumber *num6 = [NSNumber numberWithInteger:y];
        
        //把2转成对象 就可以加入数组 否则要@"2" 有时候集合不接受基本数据类型 就接受对象
        NSMutableArray *marray = [NSMutableArray arrayWithCapacity:10];
        
        [marray addObject:[NSNumber numberWithInt:2]];
        NSLog(@"%@",marray);
        //将NSnumber转换成基本数据类型
        i = [num intValue];//把num转换成int赋值给i
        f = [num1 floatValue];
        
        
    }
    return 0;
}