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Queryable.Take Method

Definition

Overloads

Take<TSource>(IQueryable<TSource>, Int32)

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

Take<TSource>(IQueryable<TSource>, Range)

Returns a specified range of contiguous elements from a sequence.

Take<TSource>(IQueryable<TSource>, Int32)

Source:
Queryable.cs
Source:
Queryable.cs
Source:
Queryable.cs

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

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static System::Linq::IQueryable<TSource> ^ Take(System::Linq::IQueryable<TSource> ^ source, int count);
public static System.Linq.IQueryable<TSource> Take<TSource> (this System.Linq.IQueryable<TSource> source, int count);
static member Take : System.Linq.IQueryable<'Source> * int -> System.Linq.IQueryable<'Source>
<Extension()>
Public Function Take(Of TSource) (source As IQueryable(Of TSource), count As Integer) As IQueryable(Of TSource)

Type Parameters

TSource

The type of the elements of source.

Parameters

source
IQueryable<TSource>

The sequence to return elements from.

count
Int32

The number of elements to return.

Returns

IQueryable<TSource>

An IQueryable<T> that contains the specified number of elements from the start of source.

Exceptions

source is null.

Examples

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

int[] grades = { 59, 82, 70, 56, 92, 98, 85 };

// Sort the grades in descending order and take the first three.
IEnumerable<int> topThreeGrades =
    grades.AsQueryable().OrderByDescending(grade => grade).Take(3);

Console.WriteLine("The top three grades are:");
foreach (int grade in topThreeGrades)
    Console.WriteLine(grade);

/*
    This code produces the following output:

    The top three grades are:
    98
    92
    85
*/
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

Remarks

The Take<TSource>(IQueryable<TSource>, Int32) method generates a MethodCallExpression that represents calling Take<TSource>(IQueryable<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<TSource>(IQueryable<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.

Applies to

Take<TSource>(IQueryable<TSource>, Range)

Source:
Queryable.cs
Source:
Queryable.cs
Source:
Queryable.cs

Returns a specified range of contiguous elements from a sequence.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static System::Linq::IQueryable<TSource> ^ Take(System::Linq::IQueryable<TSource> ^ source, Range range);
public static System.Linq.IQueryable<TSource> Take<TSource> (this System.Linq.IQueryable<TSource> source, Range range);
static member Take : System.Linq.IQueryable<'Source> * Range -> System.Linq.IQueryable<'Source>
<Extension()>
Public Function Take(Of TSource) (source As IQueryable(Of TSource), range As Range) As IQueryable(Of TSource)

Type Parameters

TSource

The type of the elements of source.

Parameters

source
IQueryable<TSource>

The sequence to return elements from.

range
Range

The range of elements to return, which has start and end indexes either from the start or the end.

Returns

IQueryable<TSource>

An IQueryable<T> that contains the specified range of elements from the source sequence.

Exceptions

source is null.

Applies to