OC中的迭代器 值对象(把基本数据类型转化为对象类型)

功能

NSArray *arr =@[@"1", @"2", @"3", @"4"];
NSEnumerator *enumerator =[arr objectEnumerator];
NSString *str;
while (str = [enumerator nextObject]) {
NSLog(@"%@", str);
}
结果:
2015-07-23 20:48:14.375 OC07_NSDate[536:20989] 1
2015-07-23 20:48:14.375 OC07_NSDate[536:20989] 2
2015-07-23 20:48:14.375 OC07_NSDate[536:20989] 3
2015-07-23 20:48:14.375 OC07_NSDate[536:20989] 4

迭代器遍历字典

NSDictionary *dic=[NSDictionary dictionaryWithObjectsAndKeys:@"1",@"2",@"3",@"4",@"5",@"6", nil];
NSEnumerator *enumerator =[dic objectEnumerator];
NSString *str =nil;
while (str=[enumerator nextObject]) {
NSLog(@"%@",str);
}
结果:
2015-07-23 20:51:12.598 OC07_NSDate[545:22386] 1
2015-07-23 20:51:12.599 OC07_NSDate[545:22386] 3
2015-07-23 20:51:12.599 OC07_NSDate[545:22386] 5

把基本数据类型转化成对象类型

NSInteger a =10;
//  integer -> NSNumber
NSNumber *number =[[NSNumber alloc] initWithInteger:a];
NSLog(@"%@",number);
// NSNumber ->integer
NSInteger *b =[number integerValue ];