J
james
My head is about to explode!! I am trying to read the header of a Dataflex file and for whatever reason, using Binary Reader, I
am getting some strange results. Here is some code:
Private Sub btnOpen_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnOpen.Click
Dim FilePath As String
Dim s As String
Dim tblName As Long = &H2D0 ' Table Name starts here
Dim numfields As Long = &HA5 ' Number of FIELDS starts here
Dim reclength As Long = &H9A 'rec length starts at 9A to 9B
Dim totalRecords As Long = &H8 ' Goes from Hex:08 to Hex:0B
Dim fieldtype As Object 'field types can be 00=ASCII,01=Numeric,02=DATE,03=Overlap
'Display Open dialog box and select text file
OpenFileDialog1.Filter = "DAT Files(*.DAT)|*.dat|Tag Files(*.TAG)|*.TAG|CFG Files(*.CFG)|*.CFG|HDR Files(*.HDR)|*.HDR|All
Files(*.*)|*.*"
OpenFileDialog1.ShowDialog()
'If Cancel button not selected, load FilePath variable
If OpenFileDialog1.FileName <> "" Then
FilePath = OpenFileDialog1.FileName
Try
Me.Cursor = Cursors.WaitCursor
Dim i As Integer
Dim fs As FileStream
fs = New FileStream(FilePath, FileMode.Open, FileAccess.Read)
Dim r As StreamReader = New StreamReader(fs)
Dim sz As Integer = fs.Length
Dim mybytearray() As Byte = New Byte(sz) {}
Dim myencoding As ASCIIEncoding = New ASCIIEncoding
Dim a As Object
Dim b As String
Dim amt As Integer ' first byte of records
Dim nxt As Integer 'second half of Num of records
'gets number of records
r.BaseStream.Seek(totalRecords, SeekOrigin.Begin)
r.BaseStream.Read(mybytearray, 0, 1)
a = myencoding.GetString(mybytearray)
ListBox1.Items.Add("Total Records: " + a.ToString)
'gets field length
r.BaseStream.Seek(reclength, SeekOrigin.Begin)
r.BaseStream.Read(mybytearray, 0, 1)
a = myencoding.GetString(mybytearray)
amt = Asc(a)
r.BaseStream.Read(mybytearray, 0, 1)
b = myencoding.GetString(mybytearray)
nxt = Asc(b)
If Asc(b) = 0 Then
nxt = Val(b)
Else
End If
ListBox1.Items.Add("Length of Records: " + amt.ToString + nxt.ToString)
r.BaseStream.Seek(numfields, SeekOrigin.Begin)
r.BaseStream.Read(mybytearray, 0, 2)
a = myencoding.GetString(mybytearray)
ListBox1.Items.Add("Number of Fields: " + Asc(a).ToString)
'Gets TableName
r.BaseStream.Seek(tblName, SeekOrigin.Begin)
r.BaseStream.Read(mybytearray, 0, 8)
a = myencoding.GetString(mybytearray)
ListBox1.Items.Add("Table Name: " + a.ToString)
r.Close()
fs.Close()
Catch ex As Exception
'display error messages if they appear
MessageBox.Show(ex.Message)
End Try
End If
Me.Cursor = Cursors.Default
Me.Text = "BinaryFileReader " + OpenFileDialog1.FileName
End Sub
The problem I am having occurs in this section of code:
r.BaseStream.Seek(totalRecords, SeekOrigin.Begin)
r.BaseStream.Read(mybytearray, 0, 1)
a = myencoding.GetString(mybytearray)
ListBox1.Items.Add("Total Records: " + a.ToString)
With the file I am reading it should return the Decimal Value 208 ( Hex D0). This is at address H8 (totalRecords). Instead it
returns a: P (using a.ToString) or whenever I try to get the value it becomes 50 or 80 !! But, never 208 as it should be
looking at the header with a Hex Editor.
The other values in the file like, Number of Fields are correct. And, Record Length is almost right. I need to figure out how
to read the bytes from 9A to 9B and then SHIFT (LSB first) them to get the number correctly.
I have Googled and read MSDN and help until I am cross eyed (not easy for someone with only one good eye! )
Any suggestions or ideas would be most welcome.
james
am getting some strange results. Here is some code:
Private Sub btnOpen_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnOpen.Click
Dim FilePath As String
Dim s As String
Dim tblName As Long = &H2D0 ' Table Name starts here
Dim numfields As Long = &HA5 ' Number of FIELDS starts here
Dim reclength As Long = &H9A 'rec length starts at 9A to 9B
Dim totalRecords As Long = &H8 ' Goes from Hex:08 to Hex:0B
Dim fieldtype As Object 'field types can be 00=ASCII,01=Numeric,02=DATE,03=Overlap
'Display Open dialog box and select text file
OpenFileDialog1.Filter = "DAT Files(*.DAT)|*.dat|Tag Files(*.TAG)|*.TAG|CFG Files(*.CFG)|*.CFG|HDR Files(*.HDR)|*.HDR|All
Files(*.*)|*.*"
OpenFileDialog1.ShowDialog()
'If Cancel button not selected, load FilePath variable
If OpenFileDialog1.FileName <> "" Then
FilePath = OpenFileDialog1.FileName
Try
Me.Cursor = Cursors.WaitCursor
Dim i As Integer
Dim fs As FileStream
fs = New FileStream(FilePath, FileMode.Open, FileAccess.Read)
Dim r As StreamReader = New StreamReader(fs)
Dim sz As Integer = fs.Length
Dim mybytearray() As Byte = New Byte(sz) {}
Dim myencoding As ASCIIEncoding = New ASCIIEncoding
Dim a As Object
Dim b As String
Dim amt As Integer ' first byte of records
Dim nxt As Integer 'second half of Num of records
'gets number of records
r.BaseStream.Seek(totalRecords, SeekOrigin.Begin)
r.BaseStream.Read(mybytearray, 0, 1)
a = myencoding.GetString(mybytearray)
ListBox1.Items.Add("Total Records: " + a.ToString)
'gets field length
r.BaseStream.Seek(reclength, SeekOrigin.Begin)
r.BaseStream.Read(mybytearray, 0, 1)
a = myencoding.GetString(mybytearray)
amt = Asc(a)
r.BaseStream.Read(mybytearray, 0, 1)
b = myencoding.GetString(mybytearray)
nxt = Asc(b)
If Asc(b) = 0 Then
nxt = Val(b)
Else
End If
ListBox1.Items.Add("Length of Records: " + amt.ToString + nxt.ToString)
r.BaseStream.Seek(numfields, SeekOrigin.Begin)
r.BaseStream.Read(mybytearray, 0, 2)
a = myencoding.GetString(mybytearray)
ListBox1.Items.Add("Number of Fields: " + Asc(a).ToString)
'Gets TableName
r.BaseStream.Seek(tblName, SeekOrigin.Begin)
r.BaseStream.Read(mybytearray, 0, 8)
a = myencoding.GetString(mybytearray)
ListBox1.Items.Add("Table Name: " + a.ToString)
r.Close()
fs.Close()
Catch ex As Exception
'display error messages if they appear
MessageBox.Show(ex.Message)
End Try
End If
Me.Cursor = Cursors.Default
Me.Text = "BinaryFileReader " + OpenFileDialog1.FileName
End Sub
The problem I am having occurs in this section of code:
r.BaseStream.Seek(totalRecords, SeekOrigin.Begin)
r.BaseStream.Read(mybytearray, 0, 1)
a = myencoding.GetString(mybytearray)
ListBox1.Items.Add("Total Records: " + a.ToString)
With the file I am reading it should return the Decimal Value 208 ( Hex D0). This is at address H8 (totalRecords). Instead it
returns a: P (using a.ToString) or whenever I try to get the value it becomes 50 or 80 !! But, never 208 as it should be
looking at the header with a Hex Editor.
The other values in the file like, Number of Fields are correct. And, Record Length is almost right. I need to figure out how
to read the bytes from 9A to 9B and then SHIFT (LSB first) them to get the number correctly.
I have Googled and read MSDN and help until I am cross eyed (not easy for someone with only one good eye! )
Any suggestions or ideas would be most welcome.
james