一,结构体和对象的相互转化
1,系统结构体
//结构体转NSValue的方法
+ (NSValue *)valueWithCGPoint:(CGPoint)point;
+ (NSValue *)valueWithCGVector:(CGVector)vector;
+ (NSValue *)valueWithCGSize:(CGSize)size;
+ (NSValue *)valueWithCGRect:(CGRect)rect;
+ (NSValue *)valueWithCGAffineTransform:(CGAffineTransform)transform;
+ (NSValue *)valueWithUIEdgeInsets:(UIEdgeInsets)insets;
+ (NSValue *)valueWithUIOffset:(UIOffset)insets NS_AVAILABLE_IOS(5_0);
//NSValue转结构体的方法
- (CGPoint)CGPointValue;
- (CGVector)CGVectorValue;
- (CGSize)CGSizeValue;
- (CGRect)CGRectValue;
- (CGAffineTransform)CGAffineTransformValue;
- (UIEdgeInsets)UIEdgeInsetsValue;
- (UIOffset)UIOffsetValue NS_AVAILABLE_IOS(5_0);
//结构体转NSValue的使用
CGPoint point = CGPointMake(0, 0);
NSMutableArray *array = [[NSMutableArray alloc]initWithCapacity:0];
NSValue *value = [NSValue valueWithCGPoint:point];
[array addObject:value];
//NSValue转结构体的使用
NSValue *tmpValue = array[0];