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  • Artykuł

Enumerable.Min<TSource> Method (IEnumerable<TSource>, Func<TSource, Int64>)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Invokes a transform function on each element of a sequence and returns the minimum Int64 value.

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

Syntax

'Declaration
<ExtensionAttribute> _
Public Shared Function Min(Of TSource) ( _
    source As IEnumerable(Of TSource), _
    selector As Func(Of TSource, Long) _
) As Long

public static long Min<TSource>(
    this IEnumerable<TSource> source,
    Func<TSource, long> selector
)

Type Parameters

  • TSource
    The type of the elements of source.

Parameters

  • selector
    Type: System.Func<TSource, Int64>
    A transform function to apply to each element.

Return Value

Type: System.Int64
The minimum value in the 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.

Exceptions

Exception Condition
ArgumentNullException

source or selector is nulla null reference (Nothing in Visual Basic).
InvalidOperationException

source contains no elements.

Remarks

The Min<TSource>(IEnumerable<TSource>, Func<TSource, Int64>) method uses the Int64 implementation of IComparable<T> 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 Int64.

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

Examples

The following code example demonstrates how to use Min<TSource>(IEnumerable<TSource>, Func<TSource, Int32>) to determine the minimum value in a sequence of projected values.

NoteNote:

This code example uses an overload of this overloaded method that is different from the specific overload that this topic describes. To extend the example to this topic, change the body of the selector function.

 
   Structure Pet
      Public Name As String
      Public Age As Integer
   End Structure

   Sub MinEx4()
      ' 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}}

      ' Find the youngest pet by passing a 
      ' lambda expression to the Min() method.
      Dim min As Integer = pets.Min(Function(pet) pet.Age)

      ' Display the result.
      outputBlock.Text &= "The youngest pet is age " & min & vbCrLf
   End Sub

   ' This code produces the following output:
   '
   ' The youngest pet is age 1


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

      public static void MinEx4()
      {
         Pet[] pets = { new Pet { Name="Barley", Age=8 },
                            new Pet { Name="Boots", Age=4 },
                            new Pet { Name="Whiskers", Age=1 } };

         int min = pets.Min(pet => pet.Age);

         outputBlock.Text += String.Format("The youngest animal is age {0}.", min) + "\n";
      }

      /*
       This code produces the following output:

       The youngest animal is age 1.  
      */

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.