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Enumerable.Take Method

Definition

Overloads

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

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

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

Returns a specified range of contiguous elements from a sequence.

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

Source:
Take.cs
Source:
Take.cs
Source:
Take.cs

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

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

Type Parameters

TSource

The type of the elements of source.

Parameters

source
IEnumerable<TSource>

The sequence to return elements from.

count
Int32

The number of elements to return.

Returns

IEnumerable<TSource>

An IEnumerable<T> that contains the specified number of elements from the start of the input sequence.

Exceptions

source is null.

Examples

The following code example demonstrates how to use Take to return elements from the start of a sequence.

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

IEnumerable<int> topThreeGrades =
    grades.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
*/
' Create an array of Integer values that represent grades.
Dim grades() As Integer = {59, 82, 70, 56, 92, 98, 85}

' Get the highest three grades by first sorting
' them in descending order and then taking the
' first three values.
Dim topThreeGrades As IEnumerable(Of Integer) =
grades _
.OrderByDescending(Function(grade) grade) _
.Take(3)

' Display the results.
Dim output As New System.Text.StringBuilder("The top three grades are:" & vbCrLf)
For Each grade As Integer In topThreeGrades
    output.AppendLine(grade)
Next
Console.WriteLine(output.ToString())

' This code produces the following output:
'
' The top three grades are:
' 98
' 92
' 85

Remarks

This method is implemented by using deferred execution. The immediate return value is an object that stores all the information that is required to perform the action. The query represented by this method is not executed until the object is enumerated either by calling its GetEnumerator method directly or by using foreach in C# or For Each in Visual Basic.

Take enumerates source and yields elements until count elements have been yielded or source contains no more elements. If count exceeds the number of elements in source, all elements of source are returned.

If count is less than or equal to zero, source is not enumerated and an empty IEnumerable<T> is returned.

The Take and Skip methods are functional complements. Given a collection sequence coll and an integer n, concatenating the results of coll.Take(n) and coll.Skip(n) yields the same sequence as coll.

In Visual Basic query expression syntax, a Take clause translates to an invocation of Take.

See also

Applies to

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

Source:
Take.cs
Source:
Take.cs
Source:
Take.cs

Returns a specified range of contiguous elements from a sequence.

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

Type Parameters

TSource

The type of the elements of source.

Parameters

source
IEnumerable<TSource>

The sequence to return elements from.

range
Range

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

Returns

IEnumerable<TSource>

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

Exceptions

source is null.

Remarks

This method is implemented by using deferred execution. The immediate return value is an object that stores all the information that is required to perform the action. The query represented by this method is not executed until the object is enumerated either by calling its GetEnumerator method directly or by using foreach in C# or For Each in Visual Basic.

Take enumerates source and yields elements whose indices belong to the specified range.

Applies to