Enumerable.ToList<TSource>(IEnumerable<TSource>) 方法

定義

命名空間:
System.Linq
組件:
System.Linq.dll
組件:
System.Core.dll
組件:
netstandard.dll

從 IEnumerable<T> 建立 List<T>。Creates a List<T> from an IEnumerable<T>.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static System::Collections::Generic::List<TSource> ^ ToList(System::Collections::Generic::IEnumerable<TSource> ^ source);
public static System.Collections.Generic.List<TSource> ToList<TSource> (this System.Collections.Generic.IEnumerable<TSource> source);
static member ToList : seq<'Source> -> System.Collections.Generic.List<'Source>
<Extension()>
Public Function ToList(Of TSource) (source As IEnumerable(Of TSource)) As List(Of TSource)

類型參數

TSource

source 項目的類型。The type of the elements of source.

參數

source
IEnumerable<TSource>

用來建立 IEnumerable<T> 的來源 List<T>。The IEnumerable<T> to create a List<T> from.

傳回

List<TSource>

List<T>，包含輸入序列中的項目。A List<T> that contains elements from the input sequence.

例外狀況

ArgumentNullException

source 為 null。source is null.

範例

下列程式碼範例示範如何使用 ToList 來強制執行立即查詢評估，並傳回包含查詢結果的 List<T>。The following code example demonstrates how to use ToList to force immediate query evaluation and return a List<T> that contains the query results.

string[] fruits = { "apple", "passionfruit", "banana", "mango",
                      "orange", "blueberry", "grape", "strawberry" };

List<int> lengths = fruits.Select(fruit => fruit.Length).ToList();

foreach (int length in lengths)
{
    Console.WriteLine(length);
}

/*
 This code produces the following output:

 5
 12
 6
 5
 6
 9
 5
 10
*/

' Create an array of strings.
Dim fruits() As String =
{"apple", "passionfruit", "banana", "mango",
 "orange", "blueberry", "grape", "strawberry"}

' Project the length of each string and 
' put the length values into a List object.
Dim lengths As List(Of Integer) =
fruits _
.Select(Function(fruit) fruit.Length) _
.ToList()

' Display the results.
Dim output As New System.Text.StringBuilder
For Each length As Integer In lengths
    output.AppendLine(length)
Next
Console.WriteLine(output.ToString())

' This code produces the following output:
'
' 5
' 12
' 6
' 5
' 6
' 9
' 5
' 10

備註

ToList<TSource>(IEnumerable<TSource>) 方法會強制執行立即查詢評估，並傳回包含查詢結果的 List<T>。The ToList<TSource>(IEnumerable<TSource>) method forces immediate query evaluation and returns a List<T> that contains the query results. 您可以將此方法附加至查詢，以便取得查詢結果的快取複本。You can append this method to your query in order to obtain a cached copy of the query results.

ToArray 具有類似的行為，但會傳回陣列，而不是 List<T>。ToArray has similar behavior but returns an array instead of a List<T>.

適用於