2019独角兽企业重金招聘Python工程师标准>>>

#import <Foundation/Foundation.h>
#import "Photo.h"int main (int argc, const char * argv[])
{NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];//while+NSEnumerator//定义对象的数组NSArray *array = [NSArray arrayWithObjects:[[Photo alloc] init], [[Photo alloc] init],[[Photo alloc] init], nil];//通过objectEnumberator获取集合的NSEnumeratorNSEnumerator *myEnumerator = [array objectEnumerator];Photo *photo;  //nextObject遍历每一项，结束返回nil//注意这里使用的是“=”号，所以最外面还要再添加一对()while((photo = [myEnumerator nextObject])){[photo draw];}[pool drain];return 0;
}

#import <Foundation/Foundation.h>
#import "Photo.h"int main (int argc, const char * argv[])
{NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];//NSSet  allObjectsNSSet *set = [NSSet setWithObjects:[[Photo alloc] init], [[Photo alloc] init],[[Photo alloc] init], nil];//allObjects仅能获取NSArray，需要再次调用objectEnumberator//并且获取的数组顺序不确定。NSEnumerator *myEnumerator = [[set allObjects] objectEnumerator];Photo *photo;while((photo = [myEnumerator nextObject])){[photo draw];}[pool drain];return 0;
}

#import <Foundation/Foundation.h>
#import "Photo.h"int main (int argc, const char * argv[])
{NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];//NSDictionary allValues//NSDictionary 添加项时是value在前j，key在后的，与C#相反NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys:[[Photo alloc] init], @"p1",[[Photo alloc] init], @"p2",[[Photo alloc] init], @"p3", nil];//allValues 只能获取字典中值的数组列表,注意列表是无序的。NSEnumerator *myEnumerator = [[dict allValues] objectEnumerator];Photo *photo;while((photo = [myEnumerator nextObject])){[photo draw];}//allKeys 遍历字典中的所有key列表，然后能过objectForKey获取值。注意列表是无序的。myEnumerator = [[dict allKeys] objectEnumerator];NSString *key;while((key = [myEnumerator nextObject])){//objectForKey从字典中获取key对应的值[[dict objectForKey:key] draw];}[pool drain];return 0;
}