한빛출판네트워크

Dim fs, s1, s2 As FileStream
Dim sr As StreamReader
Dim sw As StreamWriter
Dim br As BinaryReader
Dim bw As BinaryWriter
Dim ms As MemoryStream

Const FILE_NAME = "c:\textFile.txt"
Const BAK_FILE_NAME = "c:\textFile_bak.txt"
Const FILE_NAME_IMAGE = "c:\iMac.jpg"
Const FILE_NAME_BIN = "c:\bin.jpg"
Dim bytes(10) As Byte

Imports System.IO

"---Copy and Delete the file
If File.Exists(FILE_NAME) Then
	File.Copy(FILE_NAME, BAK_FILE_NAME, True)
	File.Delete(FILE_NAME)
End If

fs = File.Create(FILE_NAME_BIN)
fs.Close()

sw = File.CreateText(FILE_NAME)
sw.Close()

fs = File.Open(FILE_NAME, FileMode.Open, FileAccess.Read, FileShare.Read)
fs.Close()

"---create a file and write some bytes to it
fs = New FileStream(FILE_NAME, FileMode.CreateNew, FileAccess.Write)
bytes(0) = 72 "H"
bytes(1) = 101 "e"
bytes(2) = 108 "l"
bytes(3) = 108 "l"
bytes(4) = 111 "o"
bytes(5) = 13 "CR"
bytes(6) = 87 "W"
bytes(7) = 111 "o"
bytes(8) = 114 "r"
bytes(9) = 108 "l"
bytes(10) = 100 "d"

fs.Write(bytes, 0, bytes.Length)
fs.Close()

"---Using a streamWriter to write to a file
sw = New StreamWriter(FILE_NAME, True, System.Text.Encoding.ASCII)
sw.WriteLine("Welcome to VB.NET")
sw.Close()

"---open a file and read the byte(s) out
fs = New FileStream(FILE_NAME, FileMode.Open, FileAccess.Read)
fs.Read(bytes, 0, bytes.Length)
Dim i As Short
For i = 0 To bytes.Length - 1
		Console.Write(Chr(bytes(i)))
Next

"---seeking
fs.Seek(11, SeekOrigin.Current)
fs.Read(bytes, 0, 6)
For i = 0 To 5
		Console.Write(Chr(bytes(i)))
Next
fs.Close()

"---open a file and read line by line using a streamreader
sr = New StreamReader(FILE_NAME)
Dim line As String = sr.ReadLine()

While Not line Is Nothing
	Console.Write(line)
	line = sr.ReadLine()
End While
sr.Close()

"---read from and write to a binary file
s1 = New FileStream(FILE_NAME_IMAGE, FileMode.Open, FileAccess.Read)
s2 = New FileStream("c:\iMac_copy.jpg", FileMode.CreateNew, FileAccess.Write)

br = New BinaryReader(s1)
bw = New BinaryWriter(s2)

Dim byteRead As Byte
Dim j As Integer
For j = 0 To br.BaseStream.Length() - 1
	byteRead = br.ReadByte
	bw.Write(byteRead)
Next
br.Close()
bw.Close()

"--read from a binary stream and write into a memory stream
s1 = New FileStream(FILE_NAME_IMAGE, FileMode.Open, FileAccess.Read)
ms = New MemoryStream(s1.Length)
br = New BinaryReader(s1)
Dim bytesRead As Byte() = br.ReadBytes(s1.Length)
ms.Write(bytesRead, 0, s1.Length)
PictureBox1.Image = New Bitmap(ms)

Public Function stringcharToByteArray(ByVal str As String) As Byte()
	"e.g. "abcdefg" to {a,b,c,d,e,f,g}
	Dim s As Char()
	s = str.ToCharArray
	Dim b(s.Length - 1) As Byte
	Dim i As Integer
	For i = 0 To s.Length - 1
		b(i) = Convert.ToByte(s(i))
	Next
	Return b
End Function

Public Function stringToByteArray(ByVal str As String) As Byte()
	" e.g. "1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16" to 
	"{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16}
	Dim s As String()
	s = str.Split(" ")
	Dim b(s.Length - 1) As Byte
	Dim i As Integer
	For i = 0 To s.Length - 1
		b(i) = Convert.ToByte(s(i))
	Next
	Return b
End Function

Public Function byteArrayToString(ByVal b() As Byte) As String
	Dim i As Integer
	Dim s As New System.Text.StringBuilder()
	For i = 0 To b.Length - 1
		Console.WriteLine(b(i))
		If i <> b.Length - 1 Then
			s.Append(b(i) & " ")
		Else
			s.Append(b(i))
		End If
	Next
	Return s.ToString
End Function