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Enumerable.Range(Int32, Int32) Method

Definition

Generates a sequence of integral numbers within a specified range.

public:
 static System::Collections::Generic::IEnumerable<int> ^ Range(int start, int count);
public static System.Collections.Generic.IEnumerable<int> Range (int start, int count);
static member Range : int * int -> seq<int>
Public Function Range (start As Integer, count As Integer) As IEnumerable(Of Integer)

Parameters

start
Int32

The value of the first integer in the sequence.

count
Int32

The number of sequential integers to generate.

Returns

An IEnumerable<Int32> in C# or IEnumerable(Of Int32) in Visual Basic that contains a range of sequential integral numbers.

Exceptions

count is less than 0.

-or-

start + count -1 is larger than Int32.MaxValue.

Examples

The following code example demonstrates how to use Range to generate a sequence of values.

// Generate a sequence of integers from 1 to 10
// and then select their squares.
IEnumerable<int> squares = Enumerable.Range(1, 10).Select(x => x * x);

foreach (int num in squares)
{
    Console.WriteLine(num);
}

/*
 This code produces the following output:

 1
 4
 9
 16
 25
 36
 49
 64
 81
 100
*/
' Generate a sequence of integers from 1 to 10
' and project their squares.
Dim squares As IEnumerable(Of Integer) =
Enumerable.Range(1, 10).Select(Function(x) x * x)

Dim output As New System.Text.StringBuilder
For Each num As Integer In squares
    output.AppendLine(num)
Next

' Display the output.
Console.WriteLine(output.ToString())

' This code produces the following output:
'
' 1
' 4
' 9
' 16
' 25
' 36
' 49
' 64
' 81
' 100

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.

Applies to