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MemoryMappedViewAccessor Class

Definition

Represents a randomly accessed view of a memory-mapped file.

public ref class MemoryMappedViewAccessor sealed : System::IO::UnmanagedMemoryAccessor
public sealed class MemoryMappedViewAccessor : System.IO.UnmanagedMemoryAccessor
type MemoryMappedViewAccessor = class
    inherit UnmanagedMemoryAccessor
Public NotInheritable Class MemoryMappedViewAccessor
Inherits UnmanagedMemoryAccessor
Inheritance
MemoryMappedViewAccessor

Examples

The following example obtains a MemoryMappedViewAccessor from a large memory-mapped file for editing.

This code example is part of a larger example provided for the MemoryMappedFile class.

// Create a random access view, from the 256th megabyte (the offset)
// to the 768th megabyte (the offset plus length).
using (var accessor = mmf.CreateViewAccessor(offset, length))
{
    int colorSize = Marshal.SizeOf(typeof(MyColor));
    MyColor color;

    // Make changes to the view.
    for (long i = 0; i < length; i += colorSize)
    {
        accessor.Read(i, out color);
        color.Brighten(10);
        accessor.Write(i, ref color);
    }
}
' Create a random access view, from the 256th megabyte (the offset)
' to the 768th megabyte (the offset plus length).
Using accessor = mmf.CreateViewAccessor(offset, length)
    Dim colorSize As Integer = Marshal.SizeOf(GetType(MyColor))
    Dim color As MyColor
    Dim i As Long = 0

    ' Make changes to the view.
    Do While (i < length)
        accessor.Read(i, color)
        color.Brighten(10)
        accessor.Write(i, color)
        i += colorSize
    Loop
End Using

Remarks

Use the CreateViewAccessor method of a MemoryMappedFile object to get this view.

Properties

CanRead

Determines whether the accessor is readable.

(Inherited from UnmanagedMemoryAccessor)
CanWrite

Determines whether the accessory is writable.

(Inherited from UnmanagedMemoryAccessor)
Capacity

Gets the capacity of the accessor.

(Inherited from UnmanagedMemoryAccessor)
IsOpen

Determines whether the accessor is currently open by a process.

(Inherited from UnmanagedMemoryAccessor)
PointerOffset

Gets the number of bytes by which the starting position of this view is offset from the beginning of the memory-mapped file.

SafeMemoryMappedViewHandle

Gets a handle to the view of a memory-mapped file.

Methods

Dispose()

Releases all resources used by the UnmanagedMemoryAccessor.

(Inherited from UnmanagedMemoryAccessor)
Dispose(Boolean)

Releases the unmanaged resources used by the UnmanagedMemoryAccessor and optionally releases the managed resources.

(Inherited from UnmanagedMemoryAccessor)
Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
Flush()

Clears all buffers for this view and causes any buffered data to be written to the underlying file.

GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
Initialize(SafeBuffer, Int64, Int64, FileAccess)

Sets the initial values for the accessor.

(Inherited from UnmanagedMemoryAccessor)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
Read<T>(Int64, T)

Reads a structure of type T from the accessor into a provided reference.

(Inherited from UnmanagedMemoryAccessor)
ReadArray<T>(Int64, T[], Int32, Int32)

Reads structures of type T from the accessor into an array of type T.

(Inherited from UnmanagedMemoryAccessor)
ReadBoolean(Int64)

Reads a Boolean value from the accessor.

(Inherited from UnmanagedMemoryAccessor)
ReadByte(Int64)

Reads a byte value from the accessor.

(Inherited from UnmanagedMemoryAccessor)
ReadChar(Int64)

Reads a character from the accessor.

(Inherited from UnmanagedMemoryAccessor)
ReadDecimal(Int64)

Reads a decimal value from the accessor.

(Inherited from UnmanagedMemoryAccessor)
ReadDouble(Int64)

Reads a double-precision floating-point value from the accessor.

(Inherited from UnmanagedMemoryAccessor)
ReadInt16(Int64)

Reads a 16-bit integer from the accessor.

(Inherited from UnmanagedMemoryAccessor)
ReadInt32(Int64)

Reads a 32-bit integer from the accessor.

(Inherited from UnmanagedMemoryAccessor)
ReadInt64(Int64)

Reads a 64-bit integer from the accessor.

(Inherited from UnmanagedMemoryAccessor)
ReadSByte(Int64)

Reads an 8-bit signed integer from the accessor.

(Inherited from UnmanagedMemoryAccessor)
ReadSingle(Int64)

Reads a single-precision floating-point value from the accessor.

(Inherited from UnmanagedMemoryAccessor)
ReadUInt16(Int64)

Reads an unsigned 16-bit integer from the accessor.

(Inherited from UnmanagedMemoryAccessor)
ReadUInt32(Int64)

Reads an unsigned 32-bit integer from the accessor.

(Inherited from UnmanagedMemoryAccessor)
ReadUInt64(Int64)

Reads an unsigned 64-bit integer from the accessor.

(Inherited from UnmanagedMemoryAccessor)
ToString()

Returns a string that represents the current object.

(Inherited from Object)
Write(Int64, Boolean)

Writes a Boolean value into the accessor.

(Inherited from UnmanagedMemoryAccessor)
Write(Int64, Byte)

Writes a byte value into the accessor.

(Inherited from UnmanagedMemoryAccessor)
Write(Int64, Char)

Writes a character into the accessor.

(Inherited from UnmanagedMemoryAccessor)
Write(Int64, Decimal)

Writes a decimal value into the accessor.

(Inherited from UnmanagedMemoryAccessor)
Write(Int64, Double)

Writes a Double value into the accessor.

(Inherited from UnmanagedMemoryAccessor)
Write(Int64, Int16)

Writes a 16-bit integer into the accessor.

(Inherited from UnmanagedMemoryAccessor)
Write(Int64, Int32)

Writes a 32-bit integer into the accessor.

(Inherited from UnmanagedMemoryAccessor)
Write(Int64, Int64)

Writes a 64-bit integer into the accessor.

(Inherited from UnmanagedMemoryAccessor)
Write(Int64, SByte)

Writes an 8-bit integer into the accessor.

(Inherited from UnmanagedMemoryAccessor)
Write(Int64, Single)

Writes a Single into the accessor.

(Inherited from UnmanagedMemoryAccessor)
Write(Int64, UInt16)

Writes an unsigned 16-bit integer into the accessor.

(Inherited from UnmanagedMemoryAccessor)
Write(Int64, UInt32)

Writes an unsigned 32-bit integer into the accessor.

(Inherited from UnmanagedMemoryAccessor)
Write(Int64, UInt64)

Writes an unsigned 64-bit integer into the accessor.

(Inherited from UnmanagedMemoryAccessor)
Write<T>(Int64, T)

Writes a structure into the accessor.

(Inherited from UnmanagedMemoryAccessor)
WriteArray<T>(Int64, T[], Int32, Int32)

Writes structures from an array of type T into the accessor.

(Inherited from UnmanagedMemoryAccessor)

Applies to

See also