//NSNumber的使用
//创建一个NSnumber对象
NSNumber *monthNumber = [NSNumber numberWithInt:10];
NSNumber *lengNumber=[[NSNumber alloc]initWithFloat:10.5];
NSLog(@"monthNumber=%@",monthNumber);
NSLog(@"lengNumber=%@",lengNumber);
// //还原成基本类型
int month=[monthNumber intValue];
float lenth=[lengNumber floatValue];
NSLog(@"month:%d",month);
NSLog(@"lentg:",lenth);