ios 值/对象的 NSDictionary 键？
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NSDictionary Key For Value/Object?
提问by Syed Absar
Can we get the key for an object in an NSDictionaryby passing a particular value or object?
我们可以NSDictionary通过传递特定的值或对象来获取对象的键吗？
回答by jscs
-[NSDictionary allKeysForObject:]returns an NSArrayof all the keys whose objects match the passed object, where "match" is determined by isEqual:.
-[NSDictionary allKeysForObject:]返回NSArray对象与传递对象匹配的所有键中的一个，其中“匹配”由 确定isEqual:。
回答by AddisDev
To answer you question in a more specific manner, use the following to get a key for a particular object:
要以更具体的方式回答您的问题，请使用以下内容获取特定对象的密钥：
NSString *knownObject = @"the object";
NSArray *temp = [dict allKeysForObject:knownObject];
NSString *key = [temp lastObject];
//"key" is now equal to the key of the object you were looking for
回答by Denis Kutlubaev
This is how you can get a first key for object (in case it is an NSString):
这是获取对象的第一个键的方法（如果它是NSString）：
NSArray *keys = [yourDic allKeysForObject:yourObject];
NSString *yourKey;
if ([keys count] > 0) {
yourKey = keys[0];
}
This handles if the object is not found in in the dictionary.
如果在字典中找不到对象，这将处理。
