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Queryable.Take(Of TSource) Method

Returns a specified number of contiguous elements from the start of a sequence.

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

'Declaration
<ExtensionAttribute> _
Public Shared Function Take(Of TSource) ( _
	source As IQueryable(Of TSource), _
	count As Integer _
) As IQueryable(Of TSource)
'Usage
Dim source As IQueryable(Of TSource)
Dim count As Integer 
Dim returnValue As IQueryable(Of TSource)

returnValue = source.Take(count)

Type Parameters

TSource

The type of the elements of source.

Parameters

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

The sequence to return elements from.

count
Type: System.Int32

The number of elements to return.

Return Value

Type: System.Linq.IQueryable(Of TSource)
An IQueryable(Of T) that contains the specified number of elements from the start of source.

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 is Nothing.

The Take(Of TSource)(IQueryable(Of TSource), Int32) method generates a MethodCallExpression that represents calling Take(Of TSource)(IQueryable(Of TSource), Int32) itself as a constructed generic method. It then passes the MethodCallExpression to the CreateQuery(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 Take(Of TSource)(IQueryable(Of TSource), Int32) depends on the implementation of the type of the source parameter. The expected behavior is that it takes the first count elements from the start of source.

The following code example demonstrates how to use Take(Of TSource)(IQueryable(Of TSource), Int32) to return elements from the start of a sequence.

Dim grades() As Integer = {59, 82, 70, 56, 92, 98, 85}

' Sort the grades in descending order and take the first three. 
Dim topThreeGrades = _
    grades.AsQueryable().OrderByDescending(Function(grade) grade).Take(3)

Dim output As New System.Text.StringBuilder
output.AppendLine("The top three grades are:")
For Each grade As Integer In topThreeGrades
    output.AppendLine(grade)
Next 

' Display the output.
MsgBox(output.ToString())

' This code produces the following output: 

' The top three grades are: 
' 98 
' 92 
' 85

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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