Enumerable.Max(Of TSource, TResult) Method (IEnumerable(Of TSource), Func(Of TSource, TResult))
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Invokes a transform function on each element of a generic sequence and returns the maximum resulting value.
Assembly: System.Core (in System.Core.dll)
'Declaration <ExtensionAttribute> _ Public Shared Function Max(Of TSource, TResult) ( _ source As IEnumerable(Of TSource), _ selector As Func(Of TSource, TResult) _ ) As TResult
Type Parameters
- TSource
The type of the elements of source.
- TResult
The type of the value returned by selector.
Parameters
- source
- Type: System.Collections.Generic.IEnumerable(Of TSource)
A sequence of values to determine the maximum value of.
- selector
- Type: System.Func(Of TSource, TResult)
A transform function to apply to each element.
Return Value
Type: TResultThe maximum 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(Of TSource). When you use instance method syntax to call this method, omit the first parameter.| Exception | Condition |
|---|---|
| ArgumentNullException | source or selector is Nothing. |
If type TResult implements IComparable(Of T), this method uses that implementation to compare values. Otherwise, if type TResult implements IComparable, that implementation is used to compare values.
In Visual Basic query expression syntax, an Aggregate Into Max() clause translates to an invocation of Enumerable.Max.
The following code example demonstrates how to use Max(Of TSource)(IEnumerable(Of TSource), Func(Of TSource, Int32)) to determine the maximum value in a sequence of projected values.
Note: |
|---|
|
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 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. outputBlock.Text &= "The maximum pet age plus name length is " & max & vbCrLf End Sub ' This code produces the following output: ' ' The maximum pet age plus name length is 14
Note: