iphone - 在哪里可以找到 @max.intValue

Question

我使用以下代码获取最大值:

 NSArray *allValues = @[ [NSNumber numberWithInt:20],
                        [NSNumber numberWithInt:36],
                        [NSNumber numberWithInt:84],
                        [NSNumber numberWithInt:11],
                        [NSNumber numberWithInt:28]];

int max = [[allValues valueForKeyPath:@"@max.intValue"] intValue];
int min = [[allValues valueForKeyPath:@"@min.intValue"] intValue];

但是我有一个问题，什么文档可以告诉我KeyPath链接@max.intValue在哪里或@min.intValue.如果我知道我可以知道的关键路径做其他效果

Answer 1

您可以在 Key-Value Coding Programming Guide 中找到此信息:

@max

The @max operator compares the values of the property specified by the key path to the right of the operator and returns the maximum value found. The maximum value is determined using the compare: method of the objects at the specified key path. The compared property objects must support comparison with each other. If the value of the right side of the key path is nil, it is ignored.

@min

The @min operator compares the values of the property specified by the key path to the right of the operator and returns the minimum value found. The minimum value is determined using the compare: method of the objects at the specified key path. The compared property objects must support comparison with each other. If the value of the right side of the key path is nil, it is ignored.