#import <Foundation/Foundation.h> int main(int argc, const char * argv[]) { @autoreleasepool { //1.对字符串“2015-09-01 08:19:10”操作,输出"08:19:10"。要求使用两种截取方式。 //第一个 NSString *str=@"2015-09-01 08:19:10"; NSRange range1=[str rangeOfString:@"08:19:10"]; NSString *subStr=[str substringWithRange:range1]; NSLog(@"第一题-------(1)"); NSLog(@"%@",subStr); NSString *substr1=[str substringFromIndex:range1.location]; NSLog(@"第一题-------(2)"); NSLog(@"%@",substr1); /*2.数组中存取以下数据: @[@{@"name":@"陈丰",@"age":@"32"}, @{@"name":@"孙明",@"age":@"24"}, @{@"name":@"王明",@"age":@"12"}, @{@"name":@"李西",@"age":@"50"} ] 1)按年龄进行排序(降序),输出数据 2)删除“陈丰”并输出数据 */ NSDictionary *dic1=@{@"name":@"陈丰",@"age":@"32"}; NSDictionary *dic2=@{@"name":@"孙明",@"age":@"24"}; NSDictionary *dic3=@{@"name":@"王明",@"age":@"12"}; NSDictionary *dic4=@{@"name":@"李西",@"age":@"50"}; NSMutableArray *arr=[[NSMutableArray alloc]initWithObjects:dic1,dic2,dic3,dic4,nil]; NSSortDescriptor *sorts=[[NSSortDescriptor alloc]initWithKey:@"age" ascending:YES]; [arr sortUsingDescriptors:[NSArray arrayWithObjects:sorts, nil]]; NSLog(@"第二题-------(1)"); NSLog(@"排序后-------(升序)"); for(NSDictionary *dic in arr){ NSLog(@"%@,%@",[dic objectForKey:@"name"],[dic objectForKey:@"age"]); } NSLog(@"排序后-------(降序)"); NSSortDescriptor *sorts1=[[NSSortDescriptor alloc]initWithKey:@"age" ascending:NO]; [arr sortUsingDescriptors:[NSArray arrayWithObjects:sorts1, nil]]; for(NSDictionary *dic in arr){ NSLog(@"%@ %@",dic[@"name"],dic[@"age"]); } NSLog(@"第二题-------(2)"); for(int i=0;i<[arr count];i++){ NSDictionary *dic=arr[i]; if([dic[@"name"] isEqual:@"陈丰"]){ [arr removeObject:dic]; } } for(NSDictionary *dic in arr){ NSLog(@"%@ %@",dic[@"name"],dic[@"age"]); } } return 0; }