MemoryMappedFile.CreateOrOpen Method (String, Int64, MemoryMappedFileAccess)

.NET Framework 4.6 and 4.5

Creates or opens a memory-mapped file that has the specified capacity and access type in system memory.

Namespace:  System.IO.MemoryMappedFiles
Assembly:  System.Core (in System.Core.dll)

public static MemoryMappedFile CreateOrOpen(
	string mapName,
	long capacity,
	MemoryMappedFileAccess access
)

Parameters

mapName
Type: System.String

A name to assign to the memory-mapped file.

capacity
Type: System.Int64

The maximum size, in bytes, to allocate to the memory-mapped file.

access
Type: System.IO.MemoryMappedFiles.MemoryMappedFileAccess

One of the enumeration values that specifies the type of access allowed to the memory-mapped file. The default is ReadWrite.

Return Value

Type: System.IO.MemoryMappedFiles.MemoryMappedFile
A memory-mapped file that has the specified characteristics.

ExceptionCondition
ArgumentException

mapName is an empty string.

-or-

access is set to write-only with the Write enumeration value.

ArgumentNullException

mapName is null.

ArgumentOutOfRangeException

capacity is greater than the size of the logical address space.

-or-

capacity is less than or equal to zero.

-or-

access is not a valid MemoryMappedFileAccess enumeration value.

UnauthorizedAccessException

The operating system denied the specified access to the file; for example, access is set to Write or ReadWrite, but the file or directory is read-only.

Use this method to create or open a memory-mapped file that is not persisted (that is, not associated with a file on disk), which you can use to share data between processes.

.NET Framework

Supported in: 4.6, 4.5, 4

.NET Framework Client Profile

Supported in: 4
Was this page helpful?
(1500 characters remaining)
Thank you for your feedback
Show:
© 2015 Microsoft