为什么80%的码农都做不了架构师？>>> 
一 问题描述
类对象的属性id类型是NSNumber ，设置UI 的 tag（NSInteger类型）时候，数据失真。
id属性是1，tag 取出来为19。
1.1 UI tag 属性
//
@property(nonatomic) NSInteger tag;1.2 错误代码如下
//tagNumber 是 NSNumber 类型
[button setTag:tagNumber];1.3 修改代码如下
//通过integerValue方法 中转
[button setTag:[tagNumber integerValue]];1.4 问题模拟
//1.声明 NSInteger 对象
NSInteger integer = 0;
//2.声明 NSNumber 对象
NSNumber *number = [NSNumber numberWithInt:3];
integer = number;
NSLog(@"integer:%d",integer);
NSLog(@"integer:%ld",integer);
===设置的是 3 输出的却是非 3
integer:50
integer:-5764607523034234830注意：NSNumber 对象不能直接赋值给NSInteger 变量，会导致数据失真，需要通过方法中转
二 两者区别
NSInteger 是基本类型，是int类型的typedef，被typedef成long（64位） 和的int（32位）
NSNumber 是类，包含多种数据类型的对象，提供多个方法来初始化对象，和其他操作方法
NSNumber.h头文件
- (NSNumber *)initWithChar:(char)value NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithUnsignedChar:(unsigned char)value NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithShort:(short)value NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithUnsignedShort:(unsigned short)value NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithInt:(int)value NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithUnsignedInt:(unsigned int)value NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithLong:(long)value NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithUnsignedLong:(unsigned long)value NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithLongLong:(long long)value NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithUnsignedLongLong:(unsigned long long)value NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithFloat:(float)value NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithDouble:(double)value NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithBool:(BOOL)value NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithInteger:(NSInteger)value NS_AVAILABLE(10_5, 2_0) NS_DESIGNATED_INITIALIZER;
- (NSNumber *)initWithUnsignedInteger:(NSUInteger)value NS_AVAILABLE(10_5, 2_0) NS_DESIGNATED_INITIALIZER;参考stackoverflow：NSNumber NSInteger 两者其别
三 互转方法
//把int 转换成NSNumber
NSNumber *aNumber = [NSNumber numberWithInteger:21];
//把NSNumber 对象转换成 NSInteger
NSInteger anInteger = [aNumber integerValue];