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
Return Value
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.
To |
See |
|---|---|
Open a file with a StreamReader |
How to: Read Text from Files with a StreamReader (Visual Basic) |
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
Project type |
Available |
|---|---|
Windows Application |
Yes |
Class Library |
Yes |
Console Application |
Yes |
Windows Control Library |
Yes |
Web Control Library |
Yes |
Windows Service |
Yes |
Web Site |
Yes |
Permissions
The following permission may be necessary:
Permission |
Description |
|---|---|
Controls the ability to access files and folders. Associated enumeration: Unrestricted. |
For more information, see Code Access Security and Requesting Permissions.
See Also
Tasks
How to: Read Text from Files with a StreamReader (Visual Basic)