My.Computer.FileSystem.OpenTextFileReader Method

Opens a StreamReader.

' Usage
Dim value As System.IO.StreamReader = My.Computer.FileSystem.OpenTextFileReader(file)
Dim value As System.IO.StreamReader = My.Computer.FileSystem.OpenTextFileReader(file ,encoding)
' Declaration
Public Function OpenTextFileReader( _
   ByVal file As String _
) As System.IO.StreamReader
' -or-
Public Function OpenTextFileReader( _
   ByVal file As String, _
   ByVal encoding As System.Text.Encoding _
) As System.IO.StreamReader

Parameters

• file
  String. File to be read. Required.

• encoding
  Encoding. Default is UTF8. Required.

Return Value

StreamReader

Exceptions

The following conditions may create an exception:

• The file name ends with a backslash (\) (ArgumentException).

• The specified file cannot be found (FileNotFoundException).

• The user lacks necessary permissions to read from the file (SecurityException).

Remarks

Only text files can be read with a StreamReader.

Tasks

The following table lists examples of tasks involving the My.Computer.FileSystem.OpenTextFileReader method.

Example

This example opens the file Testfile.txt, reads a line from it, and displays the line in a MessageBox.

Dim fileReader As System.IO.StreamReader
fileReader = _
My.Computer.FileSystem.OpenTextFileReader("C:\\testfile.txt")
Dim stringReader As String
stringReader = fileReader.ReadLine()
MsgBox("The first line of the file is " & stringReader)

Requirements

Namespace:Microsoft.VisualBasic.MyServices

Class:FileSystemProxy (provides access to FileSystem)

Assembly: Visual Basic Runtime Library (in Microsoft.VisualBasic.dll)

Availability by Project Type

Permissions

The following permission may be necessary:

For more information, see Code Access Security and Requesting Permissions.

See Also

Tasks

How to: Read Text from Files with a StreamReader (Visual Basic)

Reference

My.Computer.FileSystem Object

System.Text.Encoding

System.IO.StreamReader

FileSystem.OpenTextFileReader

Other Resources

Reading from Files in Visual Basic