使用通用字典和或使用IDictionary进行排序 [英] using a generic Dictionary and or sorting with IDictionary

问题描述

我有一个字典，其值在运行时确定。我可以创建它作为一个 IDictionary ，并添加到它，但我不能排序。
有没有办法创建它作为一个字典，所以我可以访问 OrderBy 或有另一种方式将其分类为 IDictionary ？

  void func（PropertyDescriptor prop） 
 {
 //创建动态字典
 Type GenericTypeDictionary = typeof（Dictionary<，>）; 
 Type SpecificTypeDictionary = GenericTypeDictionary.MakeGenericType（typeof（T），prop.PropertyType）; 
 var genericDictionary = Activator.CreateInstance（SpecificTypeDictionary）as IDictionary; 
 
 //添加一些项目
 // .... 
 
 //排序项目（此行不编译）
 genericDictionary = genericDictionary.OrderBy（x => x.Value）.ToDictionary（x => x.Key，x => x.Value）; 
} 
  

解决方案

尝试做可能没有意义，您可以从 IDictionary 创建一个适配器到 IEnumerable< DictionaryEntry> ：

  IEnumerable< DictionaryEntry> EnumerateEntries（IDictionary d）
 {
 foreach（d）中的DictionaryEntry de 
 {
 yield return de; 
} 
} 
 
 // ... 
 
 genericDictionary = EnumerateEntries（genericDictionary）.OrderBy（...）.ToDictionary（...）; 
  

（由于某些原因我没有进一步调查，使用 genericDictionary.Cast< ; DictionaryEntry>（）而不是帮助方法对我来说不起作用，但这可能是Mono的怪癖。）

I have a dictionary where the value is determined at runtime. I can create it as an IDictionary and add to it fine however I can't sort. Is there a way to create it as a Dictionary so I can access OrderBy or is there another way to sort it as an IDictionary?

void func (PropertyDescriptor prop)
{
  //Create dynamic dictionary
  Type GenericTypeDictionary = typeof(Dictionary<,>);
  Type SpecificTypeDictionary = GenericTypeDictionary.MakeGenericType(typeof(T), prop.PropertyType);
  var genericDictionary = Activator.CreateInstance(SpecificTypeDictionary) as IDictionary ;

  //Add some items to it
  //....

  //Sort items (this line doesn't compile)
  genericDictionary = genericDictionary.OrderBy(x => x.Value).ToDictionary(x => x.Key, x => x.Value);
}

解决方案

Ignoring the point that what you're trying to do might not make sense, you can just create an adapter from IDictionary to IEnumerable<DictionaryEntry>:

IEnumerable<DictionaryEntry> EnumerateEntries(IDictionary d)
{
    foreach (DictionaryEntry de in d) 
    {
        yield return de;
    }
}

// ...

genericDictionary = EnumerateEntries(genericDictionary).OrderBy(…).ToDictionary(…);

(For some reason I didn't investigate further, using genericDictionary.Cast<DictionaryEntry>() instead of the helper method didn't work for me, but that might be a Mono quirk.)

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