Enumerable.ToList(Of TSource) Method (IEnumerable(Of TSource))


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

Public Shared Function ToList(Of TSource) (
	source As IEnumerable(Of TSource)
) As List(Of TSource)


Type: System.Collections.Generic.IEnumerable(Of TSource)

The IEnumerable(Of T) to create a List(Of T) from.

Return Value

Type: System.Collections.Generic.List(Of TSource)

A List(Of T) that contains elements from the input sequence.

Type Parameters


The type of the elements of source.

Exception Condition

source is null.

The ToList(Of TSource)(IEnumerable(Of TSource)) method forces immediate query evaluation and returns a List(Of 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(Of TSource) has similar behavior but returns an array instead of a List(Of T).

The following code example demonstrates how to use ToList(Of TSource) to force immediate query evaluation and return a List(Of T) that contains the query results.

' 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) _

' Display the results.
Dim output As New System.Text.StringBuilder
For Each length As Integer In lengths

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

Universal Windows Platform
Available since 8
.NET Framework
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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