#import#define NSLog(FORMAT, ...) printf("%s\n", [[NSString stringWithFormat:FORMAT, ##__VA_ARGS__] UTF8String])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。 NSString* str =@"2015-09-01 08:19:10"; //第一种方法 NSString* str1 = [str substringFromIndex:11]; NSLog(@"%@",str1); //第二种方法 NSRange range = NSMakeRange(11, 8); NSString* str2 = [str substringWithRange:range]; NSLog(@"%@",str2); /*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 */ NSArray* array = @[@{@"name":@"陈丰",@"age":@"32"}, @{@"name":@"孙明",@"age":@"24"}, @{@"name":@"王明",@"age":@"12"}, @{@"name":@"李西",@"age":@"50"} ]; //描述器排序 NSSortDescriptor* des =[NSSortDescriptor sortDescriptorWithKey:@"age" ascending:NO]; NSArray* array2 = [NSArray arrayWithObject:des]; array=[array sortedArrayUsingDescriptors:array2]; //强转排序// NSArray* array2 = [array sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {// int object1 = [obj1[@"age"]intValue];// int object2 = [obj2[@"age"]intValue];// if(object1==object2)// {// return NSOrderedSame;// }// else if (object1