我有一个NSDictionary,包含许多不同类型对象的实例(NS
Arrays,NSDictionaries,NSStrings,NSNumbers等…).许多NSDictionaries和NSStrings都有自己的嵌套NSDictionaries和NSArrays.
如何从上到下遍历整个层次结构,并将NSDictionaries和NSArrays的所有实例分别转换为NSMutableDictionaries和NSMutableArrays？
是否有任何简单的“递归制作可变副本”功能我不知道？如果没有,我只需要反复循环和打字检查吗？我可以随时更换,还是重建整个层次结构？
解决方法
以下方法创建嵌套数组,字典和集的嵌套(深层)可变副本.它还可用于在层次结构内创建非集合对象的可变副本,例如字符串.
@interface NSObject (MyDeepCopy)
-(id)deepMutableCopy;
@end
@implementation NSObject (MyDeepCopy)
-(id)deepMutableCopy
{
if ([self isKindOfClass:[NSArray class]]) {
NSArray *oldArray = (NSArray *)self;
NSMutableArray *newArray = [NSMutableArray array];
for (id obj in oldArray) {
[newArray addObject:[obj deepMutableCopy]];
}
return newArray;
} else if ([self isKindOfClass:[NSDictionary class]]) {
NSDictionary *oldDict = (NSDictionary *)self;
NSMutableDictionary *newDict = [NSMutableDictionary dictionary];
for (id obj in oldDict) {
[newDict setObject:[oldDict[obj] deepMutableCopy] forKey:obj];
}
return newDict;
} else if ([self isKindOfClass:[NSSet class]]) {
NSSet *oldSet = (NSSet *)self;
NSMutableSet *newSet = [NSMutableSet set];
for (id obj in oldSet) {
[newSet addObject:[obj deepMutableCopy]];
}
return newSet;
#if MAKE_MUTABLE_COPIES_OF_NONCOLLECTION_OBJECTS
} else if ([self conformsToProtocol:@protocol(NSMutableCopying)]) {
// e.g. NSString
return [self mutableCopy];
} else if ([self conformsToProtocol:@protocol(NSCopying)]) {
// e.g. NSNumber
return [self copy];
#endif
} else {
return self;
}
}
@end
用它就好
NSDictionary *dict = ...; NSMutableDictionary *mdict = [dict deepMutableCopy];
(不复制字典键,只复制值).
我很确定我在SO上看过这样的东西,但现在找不到它.
