c# - 无法从 Dictionary 转换为 IDictionary

Question

我正在尝试使用方法创建界面

void Import(int id, IDictionary<int, IDictionary<int, string>> items);

然后像这样调用这个方法

Dictionary<int, Dictionary<int, string>> items = viewModel.Items
  .GroupBy(t => t.Number)
  .ToDictionary(t => t.Key, t => t.ToDictionary(x => x.LanguageId, x => x.Translation));


Import(id, items);

我预计它应该可以工作，但出现错误

cannot convert from 'System.Collections.Generic.Dictionary<int, System.Collections.Generic.Dictionary<int, string>>' to 'System.Collections.Generic.IDictionary<int, System.Collections.Generic.IDictionary<int, string>>'  

为什么我这里不能使用接口(interface)IDictionary？我应该手动转换吗？

Answer 1

更改您的分配类型。

Dictionary<int, IDictionary<int, string>> items = viewModel.Items
  .GroupBy(t => t.Number)
  .ToDictionary(t => t.Key, t => (IDictionary<int, string>) t.ToDictionary(x => x.LanguageId, x => x.Translation));