如何“转换”字典进入F＃的顺序？

Question

我如何“转换”字典成序列，这样我可以通过键值进行排序？

let results = new Dictionary()

results.Add("George", 10)
results.Add("Peter", 5)
results.Add("Jimmy", 9)
results.Add("John", 2)

let ranking = 
  results
  ???????
  |> Seq.Sort ??????
  |> Seq.iter (fun x -> (... some function ...))

Answer 1

一个System.Collections.Dictionary 是一个IEnumerable >和F＃有源图案 'KEYVALUE' 是有用分手KeyValuePair对象，因此：

open System.Collections.Generic
let results = new Dictionary<string,int>()

results.Add("George", 10)
results.Add("Peter", 5)
results.Add("Jimmy", 9)
results.Add("John", 2)

results
|> Seq.sortBy (fun (KeyValue(k,v)) -> k)
|> Seq.iter (fun (KeyValue(k,v)) -> printfn "%s: %d" k v)

Answer 2

您也可以找到dict功能非常有用。让F＃做一些类型推断你：

let results = dict ["George", 10; "Peter", 5; "Jimmy", 9; "John", 2]

> val results : System.Collections.Generic.IDictionary<string,int>

Answer 3

另一种选择，它不需要一个lambda直到结束

dict ["George", 10; "Peter", 5; "Jimmy", 9; "John", 2]
|> Seq.map (|KeyValue|)
|> Seq.sortBy fst
|> Seq.iter (fun (k,v) -> ())

与来自 https://gist.github.com/theburningmonk/3363893