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


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Returns the maximum value in a generic sequence.

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

public static TSource Max<TSource>(
	this IEnumerable<TSource> source


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

A sequence of values to determine the maximum value of.

Return Value

Type: TSource

The maximum value in the sequence.

Type Parameters


The type of the elements of source.

Exception Condition

source is null.

If type TSource implements IComparable<T>, the Max<TSource>(IEnumerable<TSource>) method uses that implementation to compare values. Otherwise, if type TSource implements IComparable, that implementation is used to compare values.

If TSource is a reference type and the source sequence is empty or contains only values that are null, this method returns null.

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

The following code example demonstrates how to use Max<TSource>(IEnumerable<TSource>) to determine the maximum value in a sequence of IComparable<T> objects.

/// <summary>
/// This class implements IComparable to be able to 
/// compare one Pet to another Pet.
/// </summary>
class Pet : IComparable<Pet>
    public string Name { get; set; }
    public int Age { get; set; }

    /// <summary>
    /// Compares this Pet to another Pet by 
    /// summing each Pet's age and name length.
    /// </summary>
    /// <param name="other">The Pet to compare this Pet to.</param>
    /// <returns>-1 if this Pet is 'less' than the other Pet, 
    /// 0 if they are equal,
    /// or 1 if this Pet is 'greater' than the other Pet.</returns>
    int IComparable<Pet>.CompareTo(Pet other)
        int sumOther = other.Age + other.Name.Length;
        int sumThis = this.Age + this.Name.Length;

        if (sumOther > sumThis)
            return -1;
        else if (sumOther == sumThis)
            return 0;
            return 1;

public static void MaxEx3()
    Pet[] pets = { new Pet { Name="Barley", Age=8 },
                   new Pet { Name="Boots", Age=4 },
                   new Pet { Name="Whiskers", Age=1 } };

    Pet max = pets.Max();

        "The 'maximum' animal is {0}.",

 This code produces the following output:

 The 'maximum' animal is Barley.

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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