F＃可變列表

List <T>類表示可以通過索引訪問的對象的強(qiáng)類型列表。

它是List類的一個(gè)可變對象。 它類似于數(shù)組，因?yàn)樗梢酝ㄟ^索引訪問，但是，與數(shù)組不同，可以調(diào)整列表大小。 因此，您不需要在聲明過程中指定大小。

創(chuàng)建一個(gè)可變列表

列表是使用new關(guān)鍵字并調(diào)用列表的構(gòu)造函數(shù)創(chuàng)建。下面的例子說明了這一點(diǎn) -

(* Creating a List *)
open System.Collections.Generic

let booksList = new List<string>()
booksList.Add("Gone with the Wind")
booksList.Add("Atlas Shrugged")
booksList.Add("Fountainhead")
booksList.Add("Thornbirds")
booksList.Add("Rebecca")
booksList.Add("Narnia")

booksList |> Seq.iteri (fun index item -> printfn "%i: %s" index booksList.[index])

當(dāng)你編譯和執(zhí)行程序，它產(chǎn)生以下輸出 

0: Gone with the Wind
1: Atlas Shrugged
2: Fountainhead
3: Thornbirds
4: Rebecca
5: Narnia

列表（T）類

列表（T）類表示可以通過索引訪問的對象的強(qiáng)類型列表。它提供的方法來搜索，排序和操作的列表。

下表提供的屬性，構(gòu)造函數(shù)和列表（T）類的方法 

屬性

構(gòu)造函數(shù)

方法

例

(* Creating a List *)
open System.Collections.Generic

let booksList = new List<string>()
booksList.Add("Gone with the Wind")
booksList.Add("Atlas Shrugged")
booksList.Add("Fountainhead")
booksList.Add("Thornbirds")
booksList.Add("Rebecca")
booksList.Add("Narnia")

printfn"Total %d books" booksList.Count
booksList |> Seq.iteri (fun index item -> printfn "%i: %s" index booksList.[index])
booksList.Insert(2, "Roots")

printfn("after inserting at index 2")
printfn"Total %d books" booksList.Count

booksList |> Seq.iteri (fun index item -> printfn "%i: %s" index booksList.[index])
booksList.RemoveAt(3)

printfn("after removing from index 3")
printfn"Total %d books" booksList.Count

booksList |> Seq.iteri (fun index item -> printfn "%i: %s" index booksList.[index])

當(dāng)你編譯和執(zhí)行程序，它產(chǎn)生以下輸出 

Total 6 books
0: Gone with the Wind
1: Atlas Shrugged
2: Fountainhead
3: Thornbirds
4: Rebecca
5: Narnia
after inserting at index 2
Total 7 books
0: Gone with the Wind
1: Atlas Shrugged
2: Roots
3: Fountainhead
4: Thornbirds
5: Rebecca
6: Narnia
after removing from index 3
Total 6 books
0: Gone with the Wind
1: Atlas Shrugged
2: Roots
3: Thornbirds
4: Rebecca
5: Narnia