将字符串拆分为多维 NSMutableDictionary

Question

假设以下示例数组：

{"/documents", "/documents/files", "/pictures"}

我希望创建一个看起来像的多维 NSMutableDictionary（如果我要手动创建它）：

NSArray *keys = [NSArray arrayWithObjects: @"documents", @"pictures", nil];
NSArray *objects = [NSArray arrayWithObjects: [NSDictionary dictionaryWithObject:[NSDictionary dictionary] forKey:@"files"], [NSDictionary dictionary], nil];

NSMutableDictionary *demoDict = [NSMutableDictionary dictionaryWithObjects:objects forKeys:keys];

NSLog(@"%@", demoDict);

会记录为：

documents = {
    files = {
    };
};
pictures = {
};

如何从具有无限长度的路径长度的类似数组中自动生成它（所以字典是无限维度的？）

到目前为止我所拥有的（希望它作为一个起点有用）是； 我将逻辑的 cmets 放在代码上方，以使其更容易看： （_folderPaths 是数组）

/**
 *set the root dictionary
 *iterate through the array
 *Split the path down by the separator
 *iterate over the path parts
 *make sure there is a part to the part, eliminates initial slash or
    double slashes
 *Check if key exists
 *if not then set a new mutdict for future children with key being the pathpart
**/

NSMutableDictionary *foldersDictionary = [NSMutableDictionary dictionary];


for(NSString *path in _folderPaths){

    NSArray *pathParts = [path componentsSeparatedByString:@"/"];

    for(NSString *pathPart in pathParts){

        if([pathPart length]>0)
        {
            if(![foldersDictionary objectForKey:pathPart])
                [foldersDictionary setObject:[NSMutableDictionary dictionary] forKey:pathPart];
            //Some way to set the new root to reference the Dictionary just created here so it can be easily added to on the next iteration?
        }

    } //end for pathPart in pathParts
} //end for path in _folderPaths

NSLog(@"%@", foldersDictionary);

这将记录为：

documents = {
};
files = {
};
pictures = {
};

因此，我需要一种能够在拆分路径的每次迭代中更深入地了解字典的方法。我之前在 C# 中的节点视图上做过这个，我可以用光标引用一个孩子，但我没有找到使用指针使用 Objective-C 来做到这一点的方法。

Answer 1

你已经很接近了。您需要做的就是动态更改添加新词典的父级。你可以这样做：

NSMutableDictionary *folders = [NSMutableDictionary dictionary];

for (NSString *path in folderPaths) {
    NSMutableArray *folderStack = [NSMutableArray arrayWithObject:folders];

    for (NSString *component in [path pathComponents]) {
        if ([component isEqualToString:@"/"]) continue;

        NSMutableDictionary *folder = [[folderStack lastObject] objectForKey:component];
        if (folder == nil) {
            folder = [NSMutableDictionary dictionary];
            [[folderStack lastObject] setObject:folder forKey:component];
        }
        [folderStack addObject:folder];
    }
}

请注意，在这种方法下，这些数组都会产生相同的结果：

{"/documents", "/documents/pictures", "/documents/pictures/favorites"}
{"/documents/pictures/favorites", "/documents", "/documents/pictures"}
{"/documents/pictures/favorites"}