本文以实例详细描述了Objective-C中常用的结构体NSRange,NSPoint,NSSize(CGSize),NSRect的定义及用法,具体如下所示:
1、NSRange:
NSRange的原型为
typedef struct _NSRange { NSUInteger location; NSUInteger length; } NSRange;
NSMakeRange的函数:
NS_INLINEz是内联函数
typedef NSRange *NSRangePointer; NS_INLINE NSRange NSMakeRange(NSUInteger loc, NSUInteger len) { NSRange r; r.location = loc; r.length = len; return r; }
使用方法:
//NSRange表示的是范围 NSRange range; range.location = 18; range.length = 34; NSLog(@"location is %zi",range.location); NSLog(@"length is %zi",range.length); //快速创建 range = NSMakeRange(8, 10); NSLog(@"location is %zi",range.location); NSLog(@"length is %zi",range.length); //NSStringFromRange将上面的结构体转化成字符串类型,打印出来 NSString* str1 = NSStringFromRange(range); //%@是一个OC对象,range代表的是一个结构体,str是一个OC对象 NSLog(@"rang is %@",str1);
2、NSPoint:
NSPoint的原型:
struct CGPoint { CGFloat x; CGFloat y; };
NSMakePoint函数:
NS_INLINE NSPoint NSMakePoint(CGFloat x, CGFloat y) { NSPoint p; p.x = x; p.y = y; return p; }
CGPointMake函数:
CGPointMake(CGFloat x, CGFloat y) { CGPoint p; p.x = x; p.y = y; return p; }
使用方法:
//NSPoint指的是位置 NSPoint point; //给结构体里面的点进行赋值 point.x = 10; point.y = 10; //快速创建点 point = NSMakePoint(10, 18); //常见的是CGPointMake创建点的函数 point = CGPointMake(29, 78); NSString* str2 = NSStringFromPoint(point); NSLog(@"point is %@",str2);
3、CGSize:
CGSize的原型:
struct CGSize { CGFloat width; CGFloat height; };
NSMakeSize函数:
NS_INLINE NSSize NSMakeSize(CGFloat w, CGFloat h) { NSSize s; s.width = w; s.height = h; return s; }
CGSizeMake函数:
CGSizeMake(CGFloat width, CGFloat height) { CGSize size; size.width = width; size.height = height; return size; }
使用方法:
NSSize size; size.width = 100; size.height = 12; size = NSMakeSize(12, 12); size = CGSizeMake(11, 11); NSString* str3 = NSStringFromSize(size); NSLog(@"%@",str3);
4、CGRect:
CGRect的原型:
struct CGRect { CGPoint origin; CGSize size; };
CGRectMake的函数:
CGRectMake(CGFloat x, CGFloat y, CGFloat width, CGFloat height) { CGRect rect; rect.origin.x = x; rect.origin.y = y; rect.size.width = width; rect.size.height = height; return rect; }
NSMakeRect函数:
NS_INLINE NSRect NSMakeRect(CGFloat x, CGFloat y, CGFloat w, CGFloat h) { NSRect r; r.origin.x = x; r.origin.y = y; r.size.width = w; r.size.height = h; return r; }
使用方法
//既包含了尺寸大小和位置 NSRect rect; rect.origin.x = 12; rect.origin.y = 14; rect.size.width = 12; rect.size.height = 15; //快速创建方法 rect = CGRectMake(12, 12, 12, 12); rect = NSMakeRect(11, 11, 11, 11); //转化成字符串打印出来 NSString* str5 = NSStringFromRect(rect); NSLog(@"rect is %@",str5);