'make a file stream for writing out the value
        Dim fs As New System.IO.FileStream("yourfile.txt", System.IO.FileMode.Create, System.IO.FileAccess.Write)
        'make a stream to hold the values
        Dim streamOut As New System.IO.BinaryWriter(fs)
        Dim srFile1 As New System.IO.FileStream("file1.txt", IO.FileMode.Open)
        Dim srFile2 As New System.IO.FileStream("file2.txt", IO.FileMode.Open)
        'create readers to get the values
        Dim streamFile1 As New System.IO.BinaryReader(srFile1)
        Dim streamFile2 As New System.IO.BinaryReader(srFile2)
        'vars to hold values
        Dim iVal1, iVal2, iVal3 As Integer
 
        Try
            'read from the first file to the end
            For intJ As Integer = 0 To streamFile1.BaseStream.Length - 1
                'get values
                iVal1 = streamFile1.ReadInt32
                iVal2 = streamFile2.ReadInt32
                'put vals together
                iVal3 = iVal1 + iVal2
                'write to the output file
                streamOut.Write(iVal3)
            Next
 
            'close the files
            streamFile1.Close()
            streamFile2.Close()
            streamOut.Close()
 
        Catch ex As Exception
            Throw ex
        End Try

'Make sure that something is in the textbox
If Len(Me.Textbox1.Text.Trim) = 0 Then
    MessageBox.Show("Please enter a file first", "Invalid File", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
'set focus to textbox1
Me.Textbox1.Focus
End If
 
'This validates the filepath, done after you check to make sure that the user entered someting in textbox1
If Not System.IO.File.Exists(Me.Textbox1.Text.Trim) Then
    MessageBox.Show("The file entered is invalid", "Invalid File", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
'set focus to textbox1
Me.Textbox1.Focus
End If

Dim dblFiles(intFileLen, 1) As Double
Dim intI As Integer, dblOut As Double
 
Try
    'read the files 
    For intI = 0 To intFileLen - 1
        'get the vals & put into the array
         dblFiles(intI, 0) = streamFile1.ReadInt16
         dblFiles(intI, 1) = streamFile2.ReadInt16
     Next
 
     'write the vals
      For intI = 0 To intFileLen - 1
          'check the vals for division by 0
          If dblFiles(intI, 0) = 0 Or dblFiles(intI, 1) = 0 Then
              dblOut = 0
          Else 'no division error, get the val to write
              dblOut = dblFiles(intI, 0) / dblFiles(intI, 1)
          End If
          'write the val
           streamOut.Write(dblOut)
       Next
 
Catch ex As Exception
       Throw ex
End Try