从一种类型转换字典到另一个 [英] Converting a Dictionary from one type to another

问题描述

我怎么能转换词典（类型A中，类型B）到词典（TypeC，键入） ？有转换时（假设第二词典字符串，字符串）的隐式转换，因此这个过程应该是自动的，对不对？我只是想不通一种优雅的方式来做到这一点。

How can I convert a Dictionary(Of TypeA, TypeB) to a Dictionary(Of TypeC, TypeD)? There is an implicit cast when converting (let's say the second dictionary is String, String), so this process should be automatic, right? I just can't figure out an elegant way to do this.

语言是VB.NET，但我可以读取并转换C＃如果你更舒服。

The language is VB.NET, but I can read and convert C# if you're more comfortable with that.

推荐答案

我会使用Linq对这样的情况下。有一个 ToDictionary（）方法将任何泛型IEnumerable（和词典＆LT; TA，TB＆GT; 是一个的IEnumerable＆LT; KeyValuePair＆LT; TA，TB＆GT;＆GT; ）到字典采取可枚举元素的两个突出产生一个键和值的字典。这使得这些类型的转换非常简单：

I would use Linq for cases like this. There's a ToDictionary() method that converts any generic IEnumerable (and a Dictionary<TA,TB> is an IEnumerable<KeyValuePair<TA,TB>>) to a Dictionary by taking two projections of the Enumerable element to produce a key and value for the dictionary. It makes these kinds of conversions very simple:

Dictionary<TypeA, TypeB> myDictionary = new Dictionary<TypeA, TypeB>
                                            { 
                                               /*initialization here*/ 
                                            };
Dictionary<TypeC, TypeD> myChangedDictionary = 
    myDictionary.ToDictionary(x=>x.Key.AsTypeC(), x=>x.Value.AsTypeD())

AsTypeC（）和AsTypeD（）的占位符任何转换，需要从A / B到C / D去。你提出的第二个意思是词典＆LT;字符串，字符串＆GT; ;在这种情况下，你根本的ToString（）两者的（如果你已经覆盖的方法），或使用键/值在某些的String.Format操作。

AsTypeC() and AsTypeD() are placeholders for whatever conversion is necessary to go from A/B to C/D. You suggested the second Dictionary was a Dictionary<string,string>; in that case you'd simply ToString() both of them (if you've overridden that method) or use the Key/Value in some String.Format operation.

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