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Queryable.Min(Of TSource, TResult) Method (IQueryable(Of TSource), Expression(Of Func(Of TSource, TResult)))

Invokes a projection function on each element of a generic IQueryable(Of T) and returns the minimum resulting value.

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

'Declaration
<ExtensionAttribute> _
Public Shared Function Min(Of TSource, TResult) ( _
	source As IQueryable(Of TSource), _
	selector As Expression(Of Func(Of TSource, TResult)) _
) As TResult
'Usage
Dim source As IQueryable(Of TSource)
Dim selector As Expression(Of Func(Of TSource, TResult))
Dim returnValue As TResult

returnValue = source.Min(selector)

Type Parameters

TSource

The type of the elements of source.

TResult

The type of the value returned by the function represented by selector.

Parameters

source
Type: System.Linq.IQueryable(Of TSource)

A sequence of values to determine the minimum of.

selector
Type: System.Linq.Expressions.Expression(Of Func(Of TSource, TResult))

A projection function to apply to each element.

Return Value

Type: TResult
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 IQueryable(Of 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).

ExceptionCondition
ArgumentNullException

source or selector is Nothing.

This method has at least one parameter of type Expression(Of TDelegate) whose type argument is one of the Func(Of T, TResult) types. For these parameters, you can pass in a lambda expression and it will be compiled to an Expression(Of TDelegate).

The Min(Of TSource, TResult)(IQueryable(Of TSource), Expression(Of Func(Of TSource, TResult))) method generates a MethodCallExpression that represents calling Min(Of TSource, TResult)(IQueryable(Of TSource), Expression(Of Func(Of TSource, TResult))) itself as a constructed generic method. It then passes the MethodCallExpression to the Execute(Of TResult)(Expression) method of the IQueryProvider represented by the Provider property of the source parameter.

The query behavior that occurs as a result of executing an expression tree that represents calling Min(Of TSource, TResult)(IQueryable(Of TSource), Expression(Of Func(Of TSource, TResult))) depends on the implementation of the type of the source parameter. The expected behavior is that it invokes selector on each element in source and returns the minimum value.

The following code example demonstrates how to use Min(Of TSource, TResult)(IQueryable(Of TSource), Expression(Of Func(Of TSource, TResult))) to determine the minimum value in a sequence of projected values.

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

Shared Sub MinEx2()
    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}}

    ' Get the Pet object that has the smallest Age value. 
    Dim min As Integer = pets.AsQueryable().Min(Function(pet) pet.Age)

    MsgBox(String.Format("The youngest animal is age {0}.", min))
End Sub 

'This code produces the following output: 

'The youngest animal is age 1.  

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5

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