我有一架装有NSNumber物体的NSDictionary物体的NSArray。 我愿利用价值计算最高值。 如果我以下列例子使用插座,我将使用“ForKeyPath:@max.OHLCClose”。 我如何将NSNumber物体作为钥匙?
typedef enum _OHLCField {
OHLCOpen,
OHLCClose
} OHLCField;
NSMutableArray *newData = [NSMutableArray array];
newData addObject: [NSDictionary dictionaryWithObjectsAndKeys:
[NSDecimalNumber numberWithDouble:fOpen], [NSNumber numberWithInt:OHLCOpen],
[NSDecimalNumber numberWithDouble:fClose], [NSNumber numberWithInt:OHLCClose]];
KVC要求关键是:
关键在于确定物体的具体财产。 通常,钥匙与接收物体中的接触器方法或试算变量的名称相对应。 钥匙必须使用ASCII编码,首先使用低频信函,不得含有白色空间。
因此,很不幸的是,你可以不使用<>ForKeyPath:。
If you need to use NSNumber s as your keys you will have to code the algorithm yourself - just iterate over the array and find the maximum value associated with your key. You could wrap the algorithm in a category so it becomes "part" of NSArray.
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