Manipulate binary files?

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Juanfelipe

Beginner

Posts: 2

Date of registration: Mar 29th 2009

Location: Brazil

Occupation: VSP

Sunday, March 29th 2009, 6:21pm

HI!
I am not expert in VB, but I do some things "interesting".

I did the following functions to read and write bytes from a file:

Source code

Public Function Read_Hex(file_name As String, offset As Long, size As Integer) As String
On Error GoTo erro
Dim ROM As Long
Dim i As Integer
Dim data As Byte
Dim data1 As String
ROM = FreeFile
Open file_name For Binary As ROM
For i = 1 To size
    Get ROM, offset + i, data
    data1 = data1 & Right$("00" & Hex(data), 2)
Next
Read_Hex = Right("000000000000" & data1, size * 2)
Close ROM
Exit Function

erro:
MsgBox Err.Description, vbOKOnly, "Error: " & Err.Number
End Function

Public Function WriteHex(file_name As String, offset As Integer, size As Integer, data As String) As Boolean
On Error GoTo erro
Dim ROM As Long
Dim data1 As String
Dim data2 As Byte
ROM = FreeFile
Open file_name For Binary As ROM
offset = offset + 1
'data1 = Hex(data)
Do While (Len(data1) Mod 2 <> 0)
    data = "0" & data
Loop
'Do While Len(data) > 0
Do While data <> ""
    data2 = Val("&H" & Mid(data, 1, 2))
    Put ROM, offset, data2
    data = Right$(data1, Len(data) - 2)
    offset = offset + 1
Loop
Close ROM
Exit Function

erro:
MsgBox Err.Description, vbOKOnly, "Error: " & Err.Number
End Function

In Jabaco, gives error in lines that are in bold.

These lines would be to:
"Release" the file : ROM = FreeFile
Open the file : Open file_name For Binary As ROM
Read a byte of the file : Get ROM, offset + i, data
Write a byte in the file : Put ROM, offset, data2

Close the file : Close ROM

Someone could tell me how to use these commands in Jabaco?

Excuse me for my English but I am Brazilian, and not learned English in school. :rolleyes:

EDIT:
How can I convert a hexadecimal(string)to decimal(integer)?
In VB6 I use:

	Source code
1	num_dec = val("&H" & right("00" & num_hex,2))

But don't work :/

This post has been edited 1 times, last edit by "Juanfelipe" (Mar 29th 2009, 6:27pm)

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OlimilO

Intermediate

Posts: 277

Date of registration: Jan 18th 2009

Location: Germany

Occupation: software engineer

Monday, March 30th 2009, 12:37am

convert hexadecimal string to integer

Hi,

Quoted

How can I convert a hexadecimal(string)to decimal(integer)? But don't work :/

ah actually ... you could use the function instead: Integer.parseInt

	Jabaco Source
1 2 3 4 5 6 7 8 9 10 11 12	Dim i As Integer Dim s As String i = 65 s = "&H" & Hex$(i) MsgBox CStr(i) & " = " & s s = Replace(s, "&H", "") i = Integer.parseInt(s, 16) MsgBox CStr(i)