iOS CoreData NSPredicate一次查询多个属性 [英] iOS CoreData NSPredicate to query multiple properties at once

问题描述

我试图使用 UISearchBar 查询 NSManagedObject的多个属性
我有一个 NSManagedObject 调用 Person ，每个人都有名称 code> socialSecurity 属性。现在我的代码可以为这些属性之一或其他属性执行搜索（fetch），但不能同时进行。

   - （void）performFetch 
 {
 [NSFetchedResultsController deleteCacheWithName：@Master]; 
 
 //初始化请求
 NSFetchRequest * fetchRequest = [[NSFetchRequest alloc] init]; 
 NSEntityDescription * entity = [NSEntityDescription entityForName：@MainObjectinManagedObjectContext：self.managedObjectContext]; 
 [fetchRequest setEntity：entity]; 
 
 //对颜色项应用升序排序
 // NSSortDescriptor * sortDescriptor = [[NSSortDescriptor alloc] initWithKey：@Termascending：YES selector：nil]; 
 NSSortDescriptor * sortDescriptor; 
 sortDescriptor = [[NSSortDescriptor alloc] initWithKey：@fullNameascending：YES selector：@selector（caseInsensitiveCompare :)]; 
 
 NSArray * descriptors = [NSArray arrayWithObject：sortDescriptor]; 
 [fetchRequest setSortDescriptors：descriptors]; 
 
 //恢复查询
 NSString * query = self.searchDisplayController.searchBar.text; 
 // if（query&& query.length）fetchRequest.predicate = [NSPredicate predicateWithFormat：@Term contains [cd]％@，query]; 
 if（searchValue == 1）
 {
 if（query& query.length）fetchRequest.predicate = [NSPredicate predicateWithFormat：@name contains [cd]％@， query]; 
} 
 else {
 if（query&&query.length）fetchRequest.predicate = [NSPredicate predicateWithFormat：@socialSecurity contains [cd]％@，query]; 
} 
 
 //初始化获取的结果控制器
 NSError * error; 
 self.fetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest：fetchRequest managedObjectContext：self.managedObjectContext sectionNameKeyPath：@pLLettercacheName：nil]; 
 
 self.fetchedResultsController.delegate = self; 
 
 if（！[[self fetchedResultsController] performFetch：& error]）NSLog（@Error：％@，[error localizedDescription]）; 
 
 [self.tableView reloadData]; 
} 
  

我不知道如何将两个属性都放到这个语句中...

  if（query&& query.length）fetchRequest.predicate = [NSPredicate predicateWithFormat：@name contains [cd] ％@，query]; 
  

任何帮助或想法都将非常感激。

您可以使用通常的布尔操作数（例如AND / OR）在 NSPredicate 中追加多个搜索字词。

这样的东西应该可以做。

  [NSPredicate predicateWithFormat：@name contains [cd]％@ OR ssid contains [cd]％@，query，query]; 
  

希望有助于：）

I am trying to use a UISearchBar to query multiple properties of a NSManagedObject I have a NSManagedObject called Person, every person has a name and socialSecurity property. Right now my code can perform a search (fetch) for one of those properties or the other, but not both at the same time.

- (void) performFetch
{       
    [NSFetchedResultsController deleteCacheWithName:@"Master"];  

    // Init a fetch request
    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"MainObject" inManagedObjectContext:self.managedObjectContext];
    [fetchRequest setEntity:entity];

    // Apply an ascending sort for the color items
    //NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"Term" ascending:YES selector:nil];
    NSSortDescriptor *sortDescriptor;
    sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"fullName" ascending:YES selector:@selector(caseInsensitiveCompare:)];    

    NSArray *descriptors = [NSArray arrayWithObject:sortDescriptor];
    [fetchRequest setSortDescriptors:descriptors];

    // Recover query
    NSString *query = self.searchDisplayController.searchBar.text;
    //if (query && query.length) fetchRequest.predicate = [NSPredicate predicateWithFormat:@"Term contains[cd] %@", query];
    if(searchValue==1)
    {
        if (query && query.length) fetchRequest.predicate = [NSPredicate predicateWithFormat:@"name contains[cd] %@", query];
    }
    else {
        if (query && query.length) fetchRequest.predicate = [NSPredicate predicateWithFormat:@"socialSecurity contains[cd] %@", query];
    }        

    // Init the fetched results controller
    NSError *error;
    self.fetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:self.managedObjectContext sectionNameKeyPath:@"pLLetter" cacheName:nil];

    self.fetchedResultsController.delegate = self;

    if (![[self fetchedResultsController] performFetch:&error]) NSLog(@"Error: %@", [error localizedDescription]);

    [self.tableView reloadData];
}

I don't know how to put both properties into this statement...

if (query && query.length) fetchRequest.predicate = [NSPredicate predicateWithFormat:@"name contains[cd] %@", query];

Any help or ideas would be greatly appreciated.

解决方案

You can append multiple search terms in an NSPredicate using the usual boolean operands such as AND/OR.

Something like this should do the trick.

[NSPredicate predicateWithFormat:@"name contains[cd] %@ OR ssid contains[cd] %@", query, query];

Hope that helps :)

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