- (id)mutableDictionaryCopyIfNeeded:(id)dictObj
    if ([dictObj isKindOfClass:[NSDictionary class]] &&
        ![dictObj isKindOfClass:[NSMutableDictionary class]]) {
        dictObj = [dictObj mutableCopy];
    return dictObj;
 合并两个字典
 @param dict 被合并的字典
- (void)mergingWithDictionary:(NSDictionary *)dict
    for (id key in [dict allKeys]) {
        id obj = [self mutableDictionaryCopyIfNeeded:[dict objectForKey:key]];
        id localObj = [self mutableDictionaryCopyIfNeeded:[self objectForKey:key]];
        if ([obj isKindOfClass:[NSDictionary class]] &&
            [localObj isKindOfClass:[NSMutableDictionary class]]) {
            // Recursive merge for NSDictionary
            [localObj mergingWithDictionary:obj];
        } else if (obj) {
            [self setObject:obj forKey:key];
 合并两个字典
 @param dict       被合并的字典
 @param ignoredKey 忽略的Key
- (void)mergingWithDictionary:(NSDictionary *)dict ignoredDictKey:(NSString *)ignoredKey
    for (id key in [dict allKeys]) {
        if ([key isEqualToString:ignoredKey]) {
            continue;
        id obj = [self mutableDictionaryCopyIfNeeded:[dict objectForKey:key]];
        id localObj = [self mutableDictionaryCopyIfNeeded:[self objectForKey:key]];
        if ([obj isKindOfClass:[NSDictionary class]] &&
            [localObj isKindOfClass:[NSMutableDictionary class]]) {
            // Recursive merge for NSDictionary