考核题 4

#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。
/*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
 */
        NSLog(@"第一题:");
        NSString *str=@"2015-09-01 08:19:10";
        NSString *str1=[str substringFromIndex:10];
        NSLog(@"%@",str1);
        NSRange range;
        range.length=9;
        range.location=10;
        NSString *str2=[str substringWithRange:range];
        NSLog(@"%@",str2);
        NSLog(@"第二题:");
        
        NSArray *arr=@[@{@"name":@"陈丰",@"age":@"32"},
                       @{@"name":@"孙明",@"age":@"24"},
                       @{@"name":@"王明",@"age":@"12"},
                       @{@"name":@"李西",@"age":@"50"}
                       ];
        NSSortDescriptor *ageSort2=[[NSSortDescriptor alloc]initWithKey:@"age" ascending:YES];
        NSArray *newarr2=[NSArray arrayWithObject:ageSort2];
        NSArray *sort2=[arr sortedArrayUsingDescriptors:newarr2];
        NSLog(@"升序输出:");
        for (NSDictionary *dic in sort2) {
            NSLog(@"姓名:%@,年龄:%@",dic[@"name"],dic[@"age"]);
        }
        NSSortDescriptor *ageSort1=[[NSSortDescriptor alloc]initWithKey:@"age" ascending:NO];
        NSArray *newarr1=[NSArray arrayWithObject:ageSort1];
        NSArray *sort1=[arr sortedArrayUsingDescriptors:newarr1];
        NSLog(@"降序输出:");
        for (NSDictionary *dic in sort1) {
            NSLog(@"姓名:%@,年龄:%@",dic[@"name"],dic[@"age"]);
        }
        NSLog(@"删除后:");
        //NSMutableArray *newarr=[NSMutableArray alloc];
        for (int i=0;i<arr.count;i++) {
            NSDictionary *dic=arr[i];
            if (![[dic objectForKey:@"name"]isEqual:@"陈丰"]) {
                //[newarr addObject:dic];
                NSLog(@"姓名:%@,年龄:%@",dic[@"name"],dic[@"age"]);
            }
        }
        
    }
    return 0;
}