[OC Foundation框架 - 13] NSValue

 1 void value()
 2 {
 3     CGPoint point = CGPointMake(10, 10);
 4     NSValue *obj = [NSValue valueWithPoint:point];
 5     NSLog(@"%@", obj);
 6    
 7     CGPoint p1 = [obj pointValue];
 8     BOOL result = CGPointEqualToPoint(point, p1);
 9     NSLog(@"result = %i", result);
10 }

 1 typedef struct
 2 {
 3     int year;
 4     int month;
 5     int day;
 6 } Date;
 7 
 8 void value2()
 9 {
10     Date d1 = {2012,12,12};
11     //void * 代表任何指针
12    
13     //根据结构体类型生成对应的类型描述字符串
14     char *type = @encode(Date);
15     NSValue *v1 = [NSValue value:&d1 withObjCType:type];
16    
17     Date d2;
18     [v1 getValue:&d2];
19     NSLog(@"%i-%i-%i", d1.year, d1.month, d1.day);
20 }