Enumerable.ToList<TSource>(IEnumerable<TSource>) Metoda
Definicja
Tworzy List<T> z IEnumerable<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)
Parametry typu
- TSource
Typ elementów source
.The type of the elements of source
.
Parametry
- source
- IEnumerable<TSource>
W IEnumerable<T> celu utworzenia elementu List<T> z.The IEnumerable<T> to create a List<T> from.
Zwraca
- List<TSource>
A List<T> , który zawiera elementy z sekwencji wejściowej.A List<T> that contains elements from the input sequence.
Wyjątki
source
to null
.source
is null
.
Przykłady
Poniższy przykład kodu demonstruje, jak użyć, ToList Aby wymusić natychmiastowe Obliczanie zapytania i zwrócić element List<T> , który zawiera wyniki zapytania.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
Uwagi
ToList<TSource>(IEnumerable<TSource>)Metoda wymusza natychmiastowe Obliczanie zapytania i zwraca wartość List<T> , która zawiera wyniki zapytania.The ToList<TSource>(IEnumerable<TSource>) method forces immediate query evaluation and returns a List<T> that contains the query results. Możesz dołączyć tę metodę do zapytania, aby uzyskać buforowaną kopię wyników zapytania.You can append this method to your query in order to obtain a cached copy of the query results.
ToArray ma podobne zachowanie, ale zwraca tablicę zamiast List<T> .ToArray has similar behavior but returns an array instead of a List<T>.