c# - 如何在C#中修改字典中的键

Question

如何更改字典中多个键的值。

我有以下字典:

SortedDictionary<int,SortedDictionary<string,List<string>>>

我想遍历这个已排序的字典，如果键值大于一定数量，则将键更改为 key+1。

Answer 1

正如 Jason 所说，您无法更改现有字典条目的键。您必须像这样使用新 key 删除/添加:

// we need to cache the keys to update since we can't
// modify the collection during enumeration
var keysToUpdate = new List<int>();

foreach (var entry in dict)
{
    if (entry.Key < MinKeyValue)
    {
        keysToUpdate.Add(entry.Key);
    }
}

foreach (int keyToUpdate in keysToUpdate)
{
    SortedDictionary<string, List<string>> value = dict[keyToUpdate];

    int newKey = keyToUpdate + 1;

    // increment the key until arriving at one that doesn't already exist
    while (dict.ContainsKey(newKey))
    {
        newKey++;
    }

    dict.Remove(keyToUpdate);
    dict.Add(newKey, value);
}