Reference

OpcFileInfo Members

Type

OpcFileInfo

Namespace

Opc.UaFx.Client

Assembly

Opc.UaFx.Advanced.dll

Package

Opc.UaFx.Advanced v2.59.0

Also in

Opc.UaFx.Client

Constructors

OpcFileInfo

2 overloads

Overload	Description
OpcFileInfo(OpcFileNodeContext)	Initializes a new instance of the OpcFileInfo class, which acts as a wrapper for the file node identified by the context specified.
OpcFileInfo(OpcClient, OpcNodeId)	Initializes a new instance of the OpcFileInfo class, which acts as a wrapper for the file node identified by the fileNodeId and accessed using the client specified.

OpcFileInfo(OpcFileNodeContext)

Initializes a new instance of the OpcFileInfo class, which acts as a wrapper for the file node identified by the context specified.

public OpcFileInfo(OpcFileNodeContext context)

Public Sub New(context As OpcFileNodeContext)

Parameters

Name	Type	Description
context	OpcFileNodeContext	The OpcFileNodeContext identifying the file node to be wrapped by the new instance.

Exceptions

Exception	Condition
ArgumentNullException	The context is a null reference (Nothing in Visual Basic).

OpcFileInfo(OpcClient, OpcNodeId)

Initializes a new instance of the OpcFileInfo class, which acts as a wrapper for the file node identified by the fileNodeId and accessed using the client specified.

public OpcFileInfo(OpcClient client, OpcNodeId fileNodeId)

Public Sub New(client As OpcClient, fileNodeId As OpcNodeId)

Parameters

Name	Type	Description
client	OpcClient	The OpcClient to use when accessing the file node information.
fileNodeId	OpcNodeId	The OpcNodeId of the file node to wrap.

Exceptions

Exception	Condition
ArgumentNullException	The client or fileNodeId is a null reference (Nothing in Visual Basic).

Properties

CanUserWrite

Gets a value indicating whether the file is writable taking user access rights into account.

public bool CanUserWrite { get; }

Public ReadOnly Property CanUserWrite As Boolean

Property value

Boolean

The value true if the current file can be written by the current user; otherwise the value false.

Exceptions

Exception	Condition
InvalidOperationException	The file node described by the current OpcFileInfo object could not be found.

Remarks

When first called, OpcFileInfo calls Refresh and caches information about the file. On subsequent calls, you must call Refresh to get the latest copy of the information.

This property does not take into account whether the file is currently opened for writing by another client and thus currently locked and not writable by others.

CanWrite

Gets a value indicating whether the file is writable.

public bool CanWrite { get; }

Public ReadOnly Property CanWrite As Boolean

Property value

Boolean

The value true if the current file can be written; otherwise the value false.

Exceptions

Exception	Condition
InvalidOperationException	The file node described by the current OpcFileInfo object could not be found.

Remarks

When first called, OpcFileInfo calls Refresh and caches information about the file. On subsequent calls, you must call Refresh to get the latest copy of the information.

This property does not take any user access rights into account, i.e. although the file is writable this may be restricted to a certain user / user group. The property does not take into account whether the file is currently opened for writing by another client and thus currently locked and not writable by others.

Context

Gets the OpcFileNodeContext used to wrap and access the file node its information is to be provided by the OpcFileInfo.

public OpcFileNodeContext Context { get; }

Public ReadOnly Property Context As OpcFileNodeContext

Property value

OpcFileNodeContext

An instance of the OpcFileNodeContext class.

Exists

Gets a value indicating whether the file node represented exists.

public bool Exists { get; }

Public ReadOnly Property Exists As Boolean

Property value

Boolean

The value true if the file node exists; otherwise the value false if the file node does not exist.

Remarks

When first called, OpcFileInfo calls Refresh and caches information about the file. On subsequent calls, you must call Refresh to get the latest copy of the information.

The Exists property returns false if any error occurs while trying to determine if the specified file node exists. This can occur in situations that raise exceptions.

Length

Gets the size, in bytes, of the current file represented by the file node described.

public long Length { get; }

Public ReadOnly Property Length As Long

Property value

Int64

The size of the file of the current file node in bytes.

Exceptions

Exception	Condition
InvalidOperationException	The file node described by the current OpcFileInfo object could not be found.

Remarks

To get the latest value, call the Refresh method.

MimeType

Gets the media type of the current file represented by the file node described.

public string MimeType { get; }

Public ReadOnly Property MimeType As String

Property value

String

The media type of the file of the current file node based on RFC 2046.

Exceptions

Exception	Condition
InvalidOperationException	The file node described by the current OpcFileInfo object could not be found.

Remarks

To get the latest value, call the Refresh method.

Name

Gets the name of the file node described.

public OpcName Name { get; }

Public ReadOnly Property Name As OpcName

Property value

OpcName

The OpcName of the file node described.

Exceptions

Exception	Condition
InvalidOperationException	The file node described by the current OpcFileInfo object could not be found.

Remarks

When first called, OpcFileInfo calls Refresh and caches information about the file. On subsequent calls, you must call Refresh to get the latest copy of the information.

Methods

AppendText

Creates a StreamWriter that appends text to the file represented by this instance of the OpcFileInfo.

public StreamWriter AppendText()

Public Function AppendText() As StreamWriter

Returns

StreamWriter

A new instance of the StreamWriter class.

Exceptions

Exception	Condition
InvalidOperationException	The file node described by the current OpcFileInfo object could not be found.

Remarks

This method returns a write-only OpcFileStream object with the mode set to AppendWrite.

Open

Opens a file in the specified mode.

public OpcFileStream Open(OpcFileMode mode)

Public Function Open(mode As OpcFileMode) As OpcFileStream

Parameters

Name	Type	Description
mode	OpcFileMode	A OpcFileMode member specifying the mode in which to open the file.

Returns

OpcFileStream

A OpcFileStream opened in the specified mode.

Exceptions

Exception	Condition
InvalidOperationException	The file node described by the current OpcFileInfo object could not be found.

OpenRead

Creates a read-only OpcFileStream.

public OpcFileStream OpenRead()

Public Function OpenRead() As OpcFileStream

Returns

OpcFileStream

A new read-only OpcFileStream object.

Exceptions

Exception	Condition
InvalidOperationException	The file node described by the current OpcFileInfo object could not be found.

Remarks

This method returns a read-only OpcFileStream object with the mode set to Read.

OpenText

Creates a StreamReader with UTF8 encoding.

public StreamReader OpenText()

Public Function OpenText() As StreamReader

Returns

StreamReader

A new StreamReader with UTF8 encoding.

Exceptions

Exception	Condition
InvalidOperationException	The file node described by the current OpcFileInfo object could not be found.

OpenWrite

Creates a write-only OpcFileStream.

public OpcFileStream OpenWrite()

Public Function OpenWrite() As OpcFileStream

Returns

OpcFileStream

A write-only OpcFileStream object.

Exceptions

Exception	Condition
InvalidOperationException	The file node described by the current OpcFileInfo object could not be found.

Remarks

This method returns a write-only OpcFileStream object with the mode set to Write.

The stream created does not append the new content to the existing content. Instead, it overwrites the existing data with the new data. If you overwrite longer data (such as "This is a test of the OpenWrite method") with a shorter string (like "Second "), the file will contain a mix of the strings ("Second test of the OpenWrite method").

Refresh

Refreshes the state and information of the OpcFileInfo object.

public void Refresh()

Public Sub Refresh()

Remarks

The method takes a snapshot of the file node.

Calls must be made to Refresh before attempting to get any information, or the information will be outdated.

ToString

override

Returns the OpcNodeId or the Value of the file node described.

public override string ToString()

Public Overrides Function ToString() As String

Returns

String

A string representing the file node described.

Overrides

ToString()