[OC Foundation框架 - 1] 常用结构体

底层封装是使用了typedef定义的结构体

typedef struct _NSString{

xxx

xxx

} NSString;

 

1. NSRange 结构体

#注意结构体不是对象

3种定义方式

1         typedef struct _NSRange{

2             int location;

3             int length;

4         } NSRange;

 

(1) 先声明后赋值

(2)同时声明、按照顺序赋值

(3)使用c函数，同时声明、赋值，并指定赋值的成员变量名

1     NSRange range = {1, 2};

2     NSRange range2 = {.location = 1, .length = 2};

3     NSRange range3 = NSMakeRange(1, 2);

 

返回对象字符串形式：

NSStringFromRange(NSRange)

转换并返回一个字符串

 

2. NSPoint / CGPoint 结构体

 1 void point()

 2 {

 3     NSPoint p;

 4     p.x = 1;

 5     p.y = 2;

 6    

 7     p = NSMakePoint(4, 2);

 8    

 9     p = CGPointMake(11, 33);

10    

11     NSString *str = NSStringFromPoint(p);

12     NSLog(@"The point is %@", str);

13 }

 

3. NSSize/ CGSize 结构体

 1 void size()

 2 {

 3     NSSize size;

 4     size.width = 100;

 5     size.height  = 90;

 6    

 7     size = NSMakeSize(42, 55);

 8    

 9     size = CGSizeMake(63, 77);

10    

11     NSString *str = NSStringFromSize(size);

12     NSLog(@"The size is %@", str);

13 }

 

4. NSRect / CGRect

 1 void rect()

 2 {

 3     NSRect r;

 4     r.origin.x = 10;

 5     r.origin.y = 12;

 6     r.size.height = 44;

 7     r.size.width = 62;

 8 

 9     r = NSMakeRect(13.11, 42.11, 42.55, 11.44);

10    

11     r = CGRectMake(13.11, 42.11, 42.55, 11.44);

12    

13 }

 

origin 是一个 NSPoint