Queryable.SequenceEqual(Of TSource) Method (IQueryable(Of TSource), IEnumerable(Of TSource))
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Determines whether two sequences are equal by using the default equality comparer to compare elements.
Assembly: System.Core (in System.Core.dll)
'Declaration <ExtensionAttribute> _ Public Shared Function SequenceEqual(Of TSource) ( _ source1 As IQueryable(Of TSource), _ source2 As IEnumerable(Of TSource) _ ) As Boolean
Type Parameters
- TSource
The type of the elements of the input sequences.
Parameters
- source1
- Type: System.Linq.IQueryable(Of TSource)
An IQueryable(Of T) whose elements to compare to those of source2.
- source2
- Type: System.Collections.Generic.IEnumerable(Of TSource)
An IEnumerable(Of T) whose elements to compare to those of the first sequence.
Return Value
Type: System.Booleantrue if the two source sequences are of equal length and their corresponding elements compare equal; otherwise, false.
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.| Exception | Condition |
|---|---|
| ArgumentNullException | source1 or source2 is Nothing. |
The SequenceEqual(Of TSource)(IQueryable(Of TSource), IEnumerable(Of TSource)) method generates a MethodCallExpression that represents calling SequenceEqual(Of TSource)(IQueryable(Of TSource), IEnumerable(Of TSource)) 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 source1 parameter.
The query behavior that occurs as a result of executing an expression tree that represents calling SequenceEqual(Of TSource)(IQueryable(Of TSource), IEnumerable(Of TSource)) depends on the implementation of the type of the source1 parameter. The expected behavior is that it determines if the two source sequences are equal.
The following code example demonstrates how to use SequenceEqual(Of TSource)(IQueryable(Of TSource), IEnumerable(Of TSource)) to determine whether two sequences are equal. In this example the sequences are equal.
Class Pet Public Name As String Public Age As Integer End Class Shared Sub SequenceEqualEx1() Dim pet1 As New Pet With {.Name = "Turbo", .Age = 2} Dim pet2 As New Pet With {.Name = "Peanut", .Age = 8} ' Create two lists of pets. Dim pets1 As New List(Of Pet)(New Pet() {pet1, pet2}) Dim pets2 As New List(Of Pet)(New Pet() {pet1, pet2}) ' Determine if the lists are equal. Dim equal As Boolean = pets1.AsQueryable().SequenceEqual(pets2) ' Display the output. Dim text As String = IIf(equal, "are", "are not") outputBlock.Text &= "The lists " & text & " equal." & vbCrLf End Sub 'This code produces the following output: 'The lists are equal.
The following code example compares two sequences that are not equal.
Class Pet Public Name As String Public Age As Integer End Class Shared Sub SequenceEqualEx2() Dim pet1 As New Pet With {.Name = "Turbo", .Age = 2} Dim pet2 As New Pet With {.Name = "Peanut", .Age = 8} ' Create two lists of pets. Dim pets1 As New List(Of Pet)() pets1.Add(pet1) pets1.Add(pet2) Dim pets2 As New List(Of Pet)() pets2.Add(New Pet With {.Name = "Turbo", .Age = 2}) pets2.Add(New Pet With {.Name = "Peanut", .Age = 8}) ' Determine if the lists are equal. Dim equal As Boolean = pets1.AsQueryable().SequenceEqual(pets2) ' Display the output. Dim text As String = IIf(equal, "are", "are not") outputBlock.Text &= "The lists " & text & " equal." & vbCrLf End Sub ' This code produces the following output: ' The lists are not equal.