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Buffer Class

Definition

Manipulates arrays of primitive types.

public ref class Buffer abstract sealed
public ref class Buffer sealed
public static class Buffer
public sealed class Buffer
[System.Runtime.InteropServices.ComVisible(true)]
public static class Buffer
type Buffer = class
[<System.Runtime.InteropServices.ComVisible(true)>]
type Buffer = class
Public Class Buffer
Public NotInheritable Class Buffer
Inheritance
Buffer
Attributes

Examples

The following code example illustrates the use of several Buffer class methods.

// Example of the Buffer class methods.
using namespace System;

// Display the array elements from right to left in hexadecimal.
void DisplayArray( array<short>^arr )
{
   Console::Write( "  arr:" );
   for ( int loopX = arr->Length - 1; loopX >= 0; loopX-- )
      Console::Write( " {0:X4}", arr[ loopX ] );
   Console::WriteLine();
}

int main()
{
   
   // This array is to be modified and displayed.
   array<short>^arr = {258,259,260,261,262,263,264,265,266,267,268,269,270,271};
   Console::WriteLine( "This example of the Buffer class "
   "methods generates the following output.\n"
   "Note: The array is displayed from right to left.\n" );
   Console::WriteLine( "Initial values of array:\n" );
   
   // Display the initial array values and ByteLength.
   DisplayArray( arr );
   Console::WriteLine( "\nBuffer::ByteLength( arr ): {0}", Buffer::ByteLength( arr ) );
   
   // Copy a region of the array; set a byte within the array.
   Console::WriteLine( "\nCall these methods: \n"
   "  Buffer::BlockCopy( arr, 5, arr, 16, 9 ),\n"
   "  Buffer::SetByte( arr, 7, 170 ).\n" );
   Buffer::BlockCopy( arr, 5, arr, 16, 9 );
   Buffer::SetByte( arr, 7, 170 );
   
   // Display the array and a byte within the array.
   Console::WriteLine( "Final values of array:\n" );
   DisplayArray( arr );
   Console::WriteLine( "\nBuffer::GetByte( arr, 26 ): {0}", Buffer::GetByte( arr, 26 ) );
}

/*
This example of the Buffer class methods generates the following output.
Note: The array is displayed from right to left.

Initial values of array:

  arr: 010F 010E 010D 010C 010B 010A 0109 0108 0107 0106 0105 0104 0103 0102

Buffer::ByteLength( arr ): 28

Call these methods:
  Buffer::BlockCopy( arr, 5, arr, 16, 9 ),
  Buffer::SetByte( arr, 7, 170 ).

Final values of array:

  arr: 010F 0101 0801 0701 0601 0501 0109 0108 0107 0106 AA05 0104 0103 0102

Buffer::GetByte( arr, 26 ): 15
*/
// Example of the Buffer class methods.
using System;

class BufferClassDemo
{
    // Display the array elements from right to left in hexadecimal.
    public static void DisplayArray( short[ ] arr )
    {
        Console.Write( "  arr:" );
        for( int loopX = arr.Length - 1; loopX >= 0; loopX-- )
            Console.Write( " {0:X4}", arr[ loopX ] );
        Console.WriteLine( );
    }

    public static void Main( )
    {
        // This array is to be modified and displayed.
        short[ ] arr = { 258, 259, 260, 261, 262, 263, 264,
                         265, 266, 267, 268, 269, 270, 271 };

        Console.WriteLine( "This example of the Buffer class " +
            "methods generates the following output.\n" +
            "Note: The array is displayed from right to left.\n" );
        Console.WriteLine( "Initial values of array:\n" );

        // Display the initial array values and ByteLength.
        DisplayArray( arr );
        Console.WriteLine( "\nBuffer.ByteLength( arr ): {0}",
            Buffer.ByteLength( arr ) );

        // Copy a region of the array; set a byte within the array.
        Console.WriteLine( "\nCall these methods: \n" +
            "  Buffer.BlockCopy( arr, 5, arr, 16, 9 ),\n" +
            "  Buffer.SetByte( arr, 7, 170 ).\n" );

        Buffer.BlockCopy( arr, 5, arr, 16, 9 );
        Buffer.SetByte( arr, 7, 170 );

        // Display the array and a byte within the array.
        Console.WriteLine( "Final values of array:\n" );
        DisplayArray( arr );
        Console.WriteLine( "\nBuffer.GetByte( arr, 26 ): {0}",
            Buffer.GetByte( arr, 26 ) );
    }
}

/*
This example of the Buffer class methods generates the following output.
Note: The array is displayed from right to left.

Initial values of array:

  arr: 010F 010E 010D 010C 010B 010A 0109 0108 0107 0106 0105 0104 0103 0102

Buffer.ByteLength( arr ): 28

Call these methods:
  Buffer.BlockCopy( arr, 5, arr, 16, 9 ),
  Buffer.SetByte( arr, 7, 170 ).

Final values of array:

  arr: 010F 0101 0801 0701 0601 0501 0109 0108 0107 0106 AA05 0104 0103 0102

Buffer.GetByte( arr, 26 ): 15
*/
open System

// Display the array elements from right to left in hexadecimal.
let displayArray (arr: int16 []) =
    printf "  arr:"
    for i = arr.Length - 1 downto 0 do
        printf $" {arr[i]:X4}"
    printfn ""

// This array is to be modified and displayed.
let arr = 
    [| 258s; 259s; 260s; 261s; 262s; 263s; 264s
       265s; 266s; 267s; 268s; 269s; 270s; 271s |]

printfn "This example of the Buffer class methods generates the following output.\nNote: The array is displayed from right to left.\n"
printfn "Initial values of array:\n"

// Display the initial array values and ByteLength.
displayArray arr
printfn $"\nBuffer.ByteLength(arr): {Buffer.ByteLength arr}"

// Copy a region of the array; set a byte within the array.
printfn "\nCall these methods: \n  Buffer.BlockCopy(arr, 5, arr, 16, 9),\n  Buffer.SetByte(arr, 7, 170).\n"

Buffer.BlockCopy(arr, 5, arr, 16, 9)
Buffer.SetByte(arr, 7, 170uy)

// Display the array and a byte within the array.
printfn "Final values of array:\n"
displayArray arr
printfn $"\nBuffer.GetByte(arr, 26): {Buffer.GetByte(arr, 26)}"


// This example of the Buffer class methods generates the following output.
// Note: The array is displayed from right to left.
//
// Initial values of array:
//
//   arr: 010F 010E 010D 010C 010B 010A 0109 0108 0107 0106 0105 0104 0103 0102
//
// Buffer.ByteLength(arr): 28
//
// Call these methods:
//   Buffer.BlockCopy(arr, 5, arr, 16, 9),
//   Buffer.SetByte(arr, 7, 170).
//
// Final values of array:
//
//   arr: 010F 0101 0801 0701 0601 0501 0109 0108 0107 0106 AA05 0104 0103 0102
//
// Buffer.GetByte(arr, 26): 15
' Example of the Buffer class methods.
Module BufferClassDemo

    ' Display the array elements from right to left in hexadecimal.
    Sub DisplayArray( arr( ) As Short )

        Console.Write( "  arr:" )
        Dim loopX     As Integer
        For loopX = arr.Length - 1 To 0 Step -1
            Console.Write( " {0:X4}", arr( loopX ) )
        Next loopX
        Console.WriteLine( )
    End Sub

    Sub Main( )

        ' This array is to be modified and displayed.
        Dim arr( ) As Short = { 258, 259, 260, 261, 262, 263, 264, _
                                265, 266, 267, 268, 269, 270, 271 }
        Console.WriteLine( _
            "This example of the Buffer class methods generates " & _
            "the following output." & vbCrLf & "Note: The " & _
            "array is displayed from right to left." & vbCrLf )
        Console.WriteLine( "Initial values of array:" & vbCrLf )

        ' Display the initial array values and ByteLength.
        DisplayArray( arr )
        Console.WriteLine( vbCrLf & _
            "Buffer.ByteLength( arr ): {0}", _
            Buffer.ByteLength( arr ) )

        ' Copy a region of the array; set a byte within the array.
        Console.WriteLine( vbCrLf & _
            "Call these methods: " & vbCrLf & _
            "  Buffer.BlockCopy( arr, 5, arr, 16, 9 )," & vbCrLf & _
            "  Buffer.SetByte( arr, 7, 170 )." & vbCrLf )

        Buffer.BlockCopy( arr, 5, arr, 16, 9 )
        Buffer.SetByte( arr, 7, 170 )

        ' Display the array and a byte within the array.
        Console.WriteLine( "Final values of array:" & vbCrLf )
        DisplayArray( arr )
        Console.WriteLine( vbCrLf & _
            "Buffer.GetByte( arr, 26 ): {0}", _
            Buffer.GetByte( arr, 26 ) )
    End Sub 
End Module 

' This example of the Buffer class methods generates the following output.
' Note: The array is displayed from right to left.
' 
' Initial values of array:
' 
'   arr: 010F 010E 010D 010C 010B 010A 0109 0108 0107 0106 0105 0104 0103 0102
' 
' Buffer.ByteLength( arr ): 28
' 
' Call these methods:
'   Buffer.BlockCopy( arr, 5, arr, 16, 9 ),
'   Buffer.SetByte( arr, 7, 170 ).
' 
' Final values of array:
' 
'   arr: 010F 0101 0801 0701 0601 0501 0109 0108 0107 0106 AA05 0104 0103 0102
' 
' Buffer.GetByte( arr, 26 ): 15

Remarks

Buffer only affects arrays of primitive types; this class does not apply to objects. Each primitive type is treated as a series of bytes without regard to any behavior or limitation associated with the primitive type.

Buffer provides methods to copy bytes from one array of primitive types to another array of primitive types, get a byte from an array, set a byte in an array, and obtain the length of an array. This class provides better performance for manipulating primitive types than similar methods in the System.Array class.

Buffer is applicable to the following primitive types: Boolean, Char, SByte, Byte, Int16, UInt16, Int32, UInt32, Int64, UInt64, IntPtr, UIntPtr, Single, and Double.

Methods

BlockCopy(Array, Int32, Array, Int32, Int32)

Copies a specified number of bytes from a source array starting at a particular offset to a destination array starting at a particular offset.

ByteLength(Array)

Returns the number of bytes in the specified array.

GetByte(Array, Int32)

Retrieves the byte at the specified location in the specified array.

MemoryCopy(Void*, Void*, Int64, Int64)

Copies a number of bytes specified as a long integer value from one address in memory to another.

This API is not CLS-compliant.

MemoryCopy(Void*, Void*, UInt64, UInt64)

Copies a number of bytes specified as an unsigned long integer value from one address in memory to another.

This API is not CLS-compliant.

SetByte(Array, Int32, Byte)

Assigns a specified value to a byte at a particular location in a specified array.

Applies to