IOS/Objective-C: NSPredicate 超出范围错误

Question

我已经构建了一个类似于下面的 NSPredicate 并且它运行良好。然而，这一次，它产生了错误：

'NSRangeException', reason: '-[NSTaggedPointerString characterAtIndex:]: Index 1 out of bounds; string length 1'

以下是我构建谓词的方式：

 NSString *shortTitleClause = nil;
    NSString *longTitleClause = nil;

编辑：

添加子句：

shortTitleClause =[NSString stringWithFormat:@"(shorttitle contains[c] %@)", searchText];
 longTitleClause =[NSString stringWithFormat:@"(longtitle contains[c] %@)", searchText];

//我的实际谓词有更多的子句，但无论有多少，我都会得到同样的错误。

NSMutableArray *predArr = [@[] mutableCopy]; 

    if (shortTitleClause.length > 0){
        [predArr addObject:shortTitleClause];
    }
    if (longTitleClause.length > 0){
        [predArr addObject:longTitleClause];
    }
NSString *predStr = [predArr componentsJoinedByString:@"||"];
   NSPredicate *resultPredicate = [NSPredicate predicateWithFormat:predStr];
   searchResults = [theBooks filteredArrayUsingPredicate:resultPredicate];

When searching for the letter 'S' the predicate logs as: `(shorttitle contains[c] S)||(longtitle contains[c] S)`

我不清楚 taggedPointerString 指的是我什么。谁能看出我为什么会收到此错误？

Answer 1

您不能在准备谓词时使用 stringWithFormat 替换 %@ 值。请改用 predicateWithFormat。并且不要使用 componentsJoinedByString 加入它们 - 使用 NSCompoundPredicate 组合多个谓词：

shortTitlePredicate = [NSPredicate predicateWithFormat:@"(shorttitle contains[c] %@)", searchText];
longTitlePredicate = [NSPredicate predicateWithFormat:@"(longtitle contains[c] %@)", searchText];

NSPredicate *resultPredicate = [NSCompoundPredicate orPredicateWithSubpredicates:@[shortTitlePredicate,longTitlePredicate]];

IOS/Objective-C: NSPredicate 超出范围错误

IOS/Objective-C: Out of Range Error with NSPredicate

nspredicate

ios