如何通过名称获取房产？如果我有"@"颜色"`,我怎么得到`self.color`？

Question

我通过KVO观察NSDictionary,我存储了我的用户首选项.

当首选项字典被更改时,我想将我的类的属性更新为新值.

我有许多子类,每个子类都有不同的属性.我正在寻找一种在超类中使用单个方法的方法,可以正确地为任何子类的各种属性将NSDictionary中的值赋给属性.

//Observe when user toggles preferences
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context 
{
    NSDictionary *prefs = [change objectForKey:NSKeyValueChangeNewKey];

    //I know I can do...
    //Subclass1
    self.isEnabled = [[prefs objectForKey:@"isEnabled"] boolValue];
    self.color = [[prefs objectForKey:@"color"];
    self.width = [[prefs objectForKey:@"width"];

    // -- or -- 

    //Subclass2
    self.isEnabled = [[prefs objectForKey:@"isEnabled"] boolValue];
    self.weight = [[prefs objectForKey:@"weight"];
    self.age = [[prefs objectForKey:@"age"];
    //...etc.

    //But I would prefer to do something like this... (Pseudocode)
    for (id key in prefs)
    {
        id value = [prefs objectForKey:key];
        [self propertyNamed:key] = value; // How can I accomplish this?
    }
}

我知道我可以将该方法子类化,并让每个子类使用自定义方法处理其特定属性.我正在寻找超类来处理所有子类的方法.

显然这里有很多案例......如果字典中有一个键,并且该类中没有该属性,等等.让我们暂时忽略它.

这样做的任何想法？

Answer 1

请参见NSKeyValueCoding.

[self setValue:... forKey:@"color"];
color = [self valueForKey:@"color"];