Filesystem | VB.NET Language Pocket Reference

1.18 Filesystem

ChDir Procedure

Microsoft.VisualBasic.FileSystem

ChDir(path)

path required; String

The path of the directory to set as the new default directory

Description

Changes the current working (default) directory.

ChDrive Procedure

Microsoft.VisualBasic.FileSystem

ChDrive(drive)

drive required; String or Char

The letter of the drive (A-Z) to set as the new default drive

Description

Changes the current working (default) disk drive.

CurDir Function

Microsoft.VisualBasic.FileSystem

CurDir[(drive)]

drive optional; String or Char

The name of the drive

Return Value

A String containing the current path

Description

Returns the current directory of a particular drive or the default drive.

If no drive is specified or if drive is a zero-length string (""), CurDir returns the path for the current drive.

drive can be the single-letter drive name with or without a colon (i.e., both "C" and "C:" are valid values for drive).

If drive is invalid, the function will generate an 10Exception exception.

Because CurDir can only accept a single-character string, you cannot use network drive names, share names, or UNC drive names.

Dir Function

Microsoft.VisualBasic.FileSystem

Dir[(pathname[, attributes])]

pathname optional; String

A string expression that defines a path, which may contain a drive name, a folder name, and a filename

attributes optional; Numeric or Constant of the FileAttribute enumeration

The file attributes to be matched

Return Value

String

Description

Returns the name of a single file or folder matching the pattern and attribute passed to the function.

A zero-length string ("") is returned if a matching file is not found.

Possible values for attributes are:

FileAttributeenumeration	Value	Description
Normal	0	Normal (not hidden and not a system file)
ReadOnly	1	Read-only file
Hidden	2	Hidden
System	4	System file
Volume	8	Volume label; if specified, all other attributes are ignored
Directory	16	Directory or folder
Archive	32	Archive
Alias	64	Alias or link

FileCopy Procedure

Microsoft.VisualBasic.FileSystem

FileCopy(source, destination)

source required; String

The name of the source file to be copied

destination required; String

The name and location of the file when copied

Return Value

None

Description

Copies a file.

FileDateTime Function

Microsoft.VisualBasic.FileSystem

FileDateTime(pathname)

pathname required; String

The filename, along with an optional drive and path

Return Value

A Date containing the date and time at which the specified file was created or last modified

Description

Obtains the date and time at which a particular file was created or last modified (whichever is later).

GetAttr Function

Microsoft. VisualBasic.FileSystem

GetAttr(pathname)

pathname required; String

Filename and an optional pathname

Return Value

An integer representing the sum of the following constants or members of the FileAttribute enumeration, which reflect the attributes set for the file:

FileAttribute Numeration	Constant	Value	Description
Normal	`VbNormal`	0	Normal
ReadOnly	`VbReadOnly`	1	Read-only
Hidden	`VbHidden`	2	Hidden
System	`VbSystem`	4	System
Directory	`VbDirectory`	16	Directory or folder
Archive	`VbArchive`	32	File has changed since last backup

Description

Determines which attributes have been set for a file or directory

Kill Procedure

Microsoft.VisualBasic.FileSystem

Kill(pathname)

pathname required; String

The file or files to be deleted

Description

Deletes a file from disk. The ? and * wildcard characters can be used to specify multiple files.

MkDir Procedure

Microsoft.VisualBasic.FileSystem

MkDir(path)

path required; String

The name of the folder to be created

Description

Creates a new folder.

Rename Procedure

Microsoft.VisualBasic.FileSystem

Rename(oldpath, newpath)

oldpath required; String

The current filename and optional path

newpath required; String

The new filename and optional path

Description

Renames a disk file or folder.

RmDir Procedure

Microsoft.VisualBasic.FileSystem

RmDir(path)

path required; String

The path of the folder to be removed

Description

Removes a folder.

SetAttr Procedure

Microsoft.VisualBasic.FileSystem

SetAttr(pathname, attributes)

pathname required; String

The name of the file or directory whose attributes are to be set

attributes required; FileAttribute enumeration

Numeric expression, FileAttribute enumerated constant, or global VB constant specifying the attributes

Description

Changes the attribute properties of a file.

You can use any sum of the following constants to set the attributes of a file:

Constant	Value	Description
`VbNormal`	0	Normal
`VbReadOnly`	1	Read-only
`VbHidden`	2	Hidden
`VbSystem`	4	System
`VbArchive`	32	File has changed since last backup

Each global constant has a corresponding constant in the FileAttribute enumeration. For example, vbNormal is identical to FileAttribute.Normal. The file-attribute constants vbDirectory, vbAlias, and vbVolume cannot be used when assigning attributes.

File-attributes constants can be Ored to set more than one attribute at the same time. For example:

SetAttr "SysFile.Dat", FileAttribute.System Or FileAttribute.Hidden

Unlock Procedure

Microsoft.VisualBasic.FileSystem

Unlock(filenumber[, record)

Unlock(filenumber[, fromrecord[, torecord]])

filenumber required; Integer

Any valid file number

record required; Long

The record or byte number at which to commence the lock

fromrecord required; Long

The first record or byte number to lock

torecord required; Long

The last record or byte number to lock

Description

Use the Unlock procedure in situations where more than one part of your program may need read and write access to the same data file. The Unlock procedure removes a lock that the Lock procedure placed on a section of the file or the whole file.

Write Procedure

Microsoft.VisualBasic.FileSystem

Write(filenumber, output)

filenumber required; Integer

Any valid file number

output required; Object (any)

A comma-delimited list of expressions or a ParamArray to be written to the file.

Named Arguments

Description

Writes data to a sequential file

WriteLine Procedure

Microsoft.VisualBasic.FileSystem

WriteLine(filenumber, [output])

filenumber required; Integer

Any valid file number

output optional; Object (any)

A comma-delimited list of expressions or a ParamArray to be written to the file

Named Arguments

Description

Writes data to a sequential file and then adds a line-feed character combination