в 16:40, 26 мая 2010

2010-05-26T16:40:30Z

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2010-05-26T12:56:19Z

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==Check Exception in file reading==

<source lang="vbnet">Imports System.IO
Imports System
public class Test
public Shared Sub Main
Dim sr As IO.StreamReader
Try
sr = New IO.StreamReader("test.txt")
Console.WriteLine(sr.ReadToEnd())
Catch ex As IO.FileNotFoundException
Console.WriteLine("FileNotFoundException")
Catch ex As IO.IOException
Console.WriteLine("IOException")
Catch ex As Exception
Console.WriteLine("Error Loading File")
Finally
sr.Close()
End Try
End Sub
End class</source>
<pre class=codeResult>Hello world!</pre>

==Create StreamReader from FileStream==

<source lang="vbnet">Imports System.IO

Public Class Tester
Public Shared Sub Main
Dim f As System.IO.FileStream
Dim r As System.IO.StreamReader
Dim mylength As Integer
Dim i As Integer
f = New System.IO.FileStream("test.txt", IO.FileMode.Open, IO.FileAccess.Read)
r = New System.IO.StreamReader(f)
Console.WriteLine(r.ReadToEnd())
f.Close()
r.Close()
End Sub
End Class</source>

==Read all text in a text file by using StreamReader==

<source lang="vbnet">Imports System.IO
Module Module1
Sub Main()
Dim SourceFile As StreamReader
Try
SourceFile = New StreamReader("test.txt")
Console.WriteLine(SourceFile.ReadToEnd())
SourceFile.Close()
Catch Except As Exception
Console.WriteLine("Debug file does not yet exist")
End Try
End Sub
End Module</source>
<pre class=codeResult><HTML>
<HEAD>
Java examples (example source code) Organized by topic </title>
<meta http-equiv="content-type" content="text/html; charset=UTF-8"> <meta http-equiv="content
-style-type" content="text/css"/>
<meta name="author" content="Demo Source and Support Ltd."/>
<meta name="copyright" content="2006 Demo Source and Support Ltd."/>
<meta name="description" CONTENT=" Java examples (example source code) Organized by topic " />
<meta name="keywords" CONTENT=" Java examples (example source code) Organized by topic "/>
...</pre>

==Read text file to a char array==

<source lang="vbnet">Imports System.IO

Public Class Tester
Public Shared Sub Main
Dim f As System.IO.FileStream
Dim r As System.IO.StreamReader
Dim mylength As Integer
Dim i As Integer
Dim mybuffer(100) As Char
f = New System.IO.FileStream("test.txt", IO.FileMode.Open, IO.FileAccess.Read)
r = New System.IO.StreamReader(f)
r.Read(mybuffer, 0, 100)
Console.WriteLine(mybuffer)
f.Close()
r.Close()
End Sub
End Class</source>

==Read text file to the end==

<source lang="vbnet">Imports System.IO
Public Class Tester
Public Shared Sub Main

Try
Dim stream As StreamReader
stream = New StreamReader("test.vb")
Console.WriteLine(stream.ReadToEnd())
Catch exceptionCatch As IOException
Console.WriteLine("FILE ERROR")
End Try
End Sub
End Class</source>

==StreamReader: Peek==

<source lang="vbnet">Imports System.IO
Public Class Tester
Public Shared Sub Main
Dim fsStream As New FileStream("test.txt", FileMode.Open, FileAccess.Read)
Dim srReader As New StreamReader(fsStream)
Try
srReader.BaseStream.Seek(0, SeekOrigin.Begin)
While srReader.Peek() > -1
Console.WriteLine(srReader.ReadLine())
End While
srReader.Close()
Catch ex As IOException
Console.WriteLine(ex.Message)
End Try
End Sub
End Class</source>

==StreamReader: read to a buffer==

<source lang="vbnet">Imports System.IO

Public Class Tester
Public Shared Sub Main
Dim f As System.IO.FileStream
Dim r As System.IO.StreamReader
Dim mylength As Integer
Dim i As Integer
Dim mybuffer(100) As Char
f = New System.IO.FileStream("test.txt", IO.FileMode.Open, IO.FileAccess.Read)
r = New System.IO.StreamReader(f)
r.Read(mybuffer, 0, 100)
Console.WriteLine(mybuffer)
f.Close()
r.Close()
End Sub
End Class</source>

==Use Finally clause to close a stream==

<source lang="vbnet">Imports System.IO
Imports System.Windows.Forms
Module Module1
Sub Main()
Dim FileDB As New OpenFileDialog()
FileDB.Filter = "All files | *.* | Text files | *.txt"
FileDB.FilterIndex = 2
FileDB.InitialDirectory = "C:\Temp"
FileDB.AddExtension = True
FileDB.DefaultExt = "txt"
If (FileDB.ShowDialog() = DialogResult.OK) Then
Dim SourceFile As StreamReader
SourceFile = New StreamReader(FileDB.FileName)
If (Not SourceFile Is Nothing) Then
Try
Console.WriteLine(SourceFile.ReadToEnd())
Catch Except As Exception
Console.WriteLine("Error: " & Except.Message)
Finally
Console.WriteLine("In finally statements")
SourceFile.Close()
End Try
End If
Else
Console.WriteLine("User selected Cancel")
End If
End Sub
End Module</source>

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VB.Net Tutorial/Stream File/StreamReader - История изменений

в 16:40, 26 мая 2010

Admin: 1 версия