ToList(TSource) Method

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

 

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

Namespace:   System.Linq
Assembly:  System.Core (in System.Core.dll)

public static List<TSource> ToList<TSource>(
	this IEnumerable<TSource> source
)

Parameters

source
Type: System.Collections.Generic.IEnumerable<TSource>

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

Return Value

Type: System.Collections.Generic.List<TSource>

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

Type Parameters

TSource

The type of the elements of source.

Exception Condition
ArgumentNullException

source is null.

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

The following code example demonstrates how to use ToList<TSource> 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
*/

Universal Windows Platform
Available since 4.5
.NET Framework
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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