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

Definition

Important

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Creates a List<T> from an IEnumerable<T>.

C#
public static System.Collections.Generic.List<TSource> ToList<TSource>(this System.Collections.Generic.IEnumerable<TSource> source);

Type Parameters

TSource

The type of the elements of source.

Parameters

source
IEnumerable<TSource>

The IEnumerable<T> to create a List<T> from.

Returns

List<TSource>

A List<T> that contains elements from the input sequence.

Exceptions

source is null.

Examples

The following code example demonstrates how to use ToList to force immediate query evaluation and return a List<T> that contains the query results.

C#
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
*/

Remarks

The ToList<TSource>(IEnumerable<TSource>) method forces immediate query evaluation and returns a List<T> that contains the query results. You can append this method to your query in order to obtain a cached copy of the query results.

ToArray has similar behavior but returns an array instead of a List<T>.

Applies to

Produit Versions
.NET Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 1.0, 1.1, 1.2, 1.3, 1.4, 1.6, 2.0, 2.1
UWP 10.0