EnumerableMax Method
 

Invokes a transform function on each element of a sequence and returns the maximum Int32 value.

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

Syntax
public static int Max<TSource>(
	this IEnumerable<TSource> source,
	Func<TSource, int> selector
)
public:
generic<typename TSource>
[ExtensionAttribute]
static int Max(
	IEnumerable<TSource>^ source,
	Func<TSource, int>^ selector
)
static member Max<'TSource> : 
        source:IEnumerable<'TSource> *
        selector:Func<'TSource, int> -> int
<ExtensionAttribute>
Public Shared Function Max(Of TSource) (
	source As IEnumerable(Of TSource),
	selector As Func(Of TSource, Integer)
) As Integer

Parameters

source
Type:

A sequence of values to determine the maximum value of.

selector
Type:

A transform function to apply to each element.

Return Value

Type:

The maximum value in the sequence.

Type Parameters

TSource

The type of the elements of source.

Exceptions
Exception Condition
ArgumentNullException

source or selector is null.

InvalidOperationException

source contains no elements.

Remarks

The Max method uses the Int32 implementation of IComparable to compare values.

You can apply this method to a sequence of arbitrary values if you provide a function, selector, that projects the members of source into a numeric type, specifically Int32.

In Visual Basic query expression syntax, an Aggregate Into Max() clause translates to an invocation of Max.

Examples

The following code example demonstrates how to use Max to determine the maximum value in a sequence of projected values.

class Pet
{
    public string Name { get; set; }
    public int Age { get; set; }
}

public static void MaxEx4()
{
    Pet[] pets = { new Pet { Name="Barley", Age=8 },
                   new Pet { Name="Boots", Age=4 },
                   new Pet { Name="Whiskers", Age=1 } };

    int max = pets.Max(pet => pet.Age + pet.Name.Length);

    Console.WriteLine(
        "The maximum pet age plus name length is {0}.",
        max);
}

/*
 This code produces the following output:

 The maximum pet age plus name length is 14.
*/
Structure Pet
    Public Name As String
    Public Age As Integer
End Structure

Sub MaxEx4()
    ' Create an array of Pet objects.
    Dim pets() As Pet = {New Pet With {.Name = "Barley", .Age = 8}, _
                         New Pet With {.Name = "Boots", .Age = 4}, _
                         New Pet With {.Name = "Whiskers", .Age = 1}}

    ' Determine the "maximum" pet by passing a
    ' lambda expression to Max() that sums the pet's age
    ' and name length.
    Dim max As Integer = pets.Max(Function(pet) _
                                      pet.Age + pet.Name.Length)

    ' Display the result.
    MsgBox("The maximum pet age plus name length is " & max)
End Sub

' This code produces the following output:
'
' The maximum pet age plus name length is 14
Version Information
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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