Enumerable.ToList<TSource> Method
Creates a List<T> from an IEnumerable<T>.
Namespace: System.Linq
Assembly: System.Core (in System.Core.dll)
Type Parameters
- TSource
The type of the elements of 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.
Usage Note
In Visual Basic and C#, you can call this method as an instance method on any object of type IEnumerable<TSource>. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).| 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
*/
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
