473,320 Members | 2,048 Online
Bytes | Software Development & Data Engineering Community
Post Job

Home Posts Topics Members FAQ

Join Bytes to post your question to a community of 473,320 software developers and data experts.

Convert DAO from VB6 to VB8?

I have a little VB6 program that dumps the schema of an Access 97 database.
The following lines of code are relevant.

Private m_wsDb As DAO.Workspace
Private m_db As DAO.Database

Set m_wsDb = DBEngine.CreateWorkspace("MainWS", "admin", vbNullString)
Set m_db = m_wsDb.OpenDatabase(m_zDbFilePath, False, False, "")

Dim tdf As TableDef
Dim fld As DAO.Field

For Each tdf In m_db.TableDefs
On Error GoTo Form_Activate_Err_Tabledef
Debug.Print "Table "; tdf.Name; " ("; tdf.RecordCount; "records )."
On Error GoTo Form_Activate_Err_Field
For Each fld In tdf.Fields
Debug.Print " Field "; fld.Name; " ("; GetFieldType(fld.Type); ": ";
fld.Size; ")."
Next fld
Next tdf

I converted the program to VB8 (.NET if you prefer). As far as I can see,
the only relevant lines that it changed are these two.

m_wsDb = DAODBEngine_definst.CreateWorkspace("MainWS", "admin",
vbNullString)

Dim tdf As DAO.TableDef

When I try to read the Access 97 database with the VB8 program, it opens the
workspace and the database, but when I try to fetch a field, I get:

A first chance exception of type
'System.Runtime.InteropServices.COMException' occurred in
ExportSchema.exe

And Err = 3219 (Invalid operation.).

I also have the same database in Access 2000 and 2003 formats. When I try to
read either of them with the VB8 program, I get:

A first chance exception of type
'System.Runtime.InteropServices.COMException' occurred in
ExportSchema.exe

And Err = 3343 (Unrecognized database format '<path>'.

What have I missed in converting VB6 -VB8?

Dick.


Aug 7 '06 #1
2 6386
Dick,

Noboby is using the name VB8 as nobody is using NT5 or NT51 what is your
purpose with this message, to get help or to start a discussion? Try to make
a clear message as readable for those you ask help from as possible.

As well can you when you have troubles to look at true dotNet code, although
this is converted, is seldom somebody in these newsgroups intrested to take
old converted code.

Here a sample of that

http://www.vb-tips.com/dbpages.aspx?...c-e9d7983c1e05

I hope this helps,

Cor

"Dick Monahan" <di**@dickmonahan.comschreef in bericht
news:Or**************@TK2MSFTNGP06.phx.gbl...
>I have a little VB6 program that dumps the schema of an Access 97 database.
The following lines of code are relevant.

Private m_wsDb As DAO.Workspace
Private m_db As DAO.Database

Set m_wsDb = DBEngine.CreateWorkspace("MainWS", "admin", vbNullString)
Set m_db = m_wsDb.OpenDatabase(m_zDbFilePath, False, False, "")

Dim tdf As TableDef
Dim fld As DAO.Field

For Each tdf In m_db.TableDefs
On Error GoTo Form_Activate_Err_Tabledef
Debug.Print "Table "; tdf.Name; " ("; tdf.RecordCount; "records )."
On Error GoTo Form_Activate_Err_Field
For Each fld In tdf.Fields
Debug.Print " Field "; fld.Name; " ("; GetFieldType(fld.Type); ": ";
fld.Size; ")."
Next fld
Next tdf

I converted the program to VB8 (.NET if you prefer). As far as I can see,
the only relevant lines that it changed are these two.

m_wsDb = DAODBEngine_definst.CreateWorkspace("MainWS", "admin",
vbNullString)

Dim tdf As DAO.TableDef

When I try to read the Access 97 database with the VB8 program, it opens
the
workspace and the database, but when I try to fetch a field, I get:

A first chance exception of type
'System.Runtime.InteropServices.COMException' occurred in
ExportSchema.exe

And Err = 3219 (Invalid operation.).

I also have the same database in Access 2000 and 2003 formats. When I try
to
read either of them with the VB8 program, I get:

A first chance exception of type
'System.Runtime.InteropServices.COMException' occurred in
ExportSchema.exe

And Err = 3343 (Unrecognized database format '<path>'.

What have I missed in converting VB6 -VB8?

Dick.


Aug 7 '06 #2
I suspect in this case, you are having a problem with the DAO reference.
If I recall correctly, DAO was dropped from MDAC around version 2.6. You
might need to find an older copy of MDAC and use that to install DAO if you
want to continue using that for your data access API.

If you are migrating an application to .Net, you should consider migrating
your data access code from DAO to Ado.Net. There are no automatic upgrade
paths that I know of from DAO to ADO.Net.

Jim Wooley
http://devauthority.com/blogs/jwooley/default.aspx
I have a little VB6 program that dumps the schema of an Access 97
database. The following lines of code are relevant.

Private m_wsDb As DAO.Workspace
Private m_db As DAO.Database
Set m_wsDb = DBEngine.CreateWorkspace("MainWS", "admin", vbNullString)
Set m_db = m_wsDb.OpenDatabase(m_zDbFilePath, False, False, "")

Dim tdf As TableDef
Dim fld As DAO.Field
For Each tdf In m_db.TableDefs
On Error GoTo Form_Activate_Err_Tabledef
Debug.Print "Table "; tdf.Name; " ("; tdf.RecordCount; "records )."
On Error GoTo Form_Activate_Err_Field
For Each fld In tdf.Fields
Debug.Print " Field "; fld.Name; " ("; GetFieldType(fld.Type); ": ";
fld.Size; ")."
Next fld
Next tdf
I converted the program to VB8 (.NET if you prefer). As far as I can
see, the only relevant lines that it changed are these two.

m_wsDb = DAODBEngine_definst.CreateWorkspace("MainWS", "admin",
vbNullString)

Dim tdf As DAO.TableDef

When I try to read the Access 97 database with the VB8 program, it
opens the workspace and the database, but when I try to fetch a field,
I get:

A first chance exception of type
'System.Runtime.InteropServices.COMException' occurred in
ExportSchema.exe

And Err = 3219 (Invalid operation.).

I also have the same database in Access 2000 and 2003 formats. When I
try to read either of them with the VB8 program, I get:

A first chance exception of type
'System.Runtime.InteropServices.COMException' occurred in
ExportSchema.exe

And Err = 3343 (Unrecognized database format '<path>'.

What have I missed in converting VB6 -VB8?

Dick.

Aug 7 '06 #3

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

19
by: Lauren Quantrell | last post by:
I have a stored procedure using Convert where the exact same Convert string works in the SELECT portion of the procedure but fails in the WHERE portion. The entire SP is listed below....
1
by: Logan X via .NET 247 | last post by:
It's official....Convert blows. I ran a number of tests converting a double to an integer usingboth Convert & CType. I *ASSUMED* that CType would piggy-back ontop of Convert, and that performance...
4
by: Eric Lilja | last post by:
Hello, I've made a templated class Option (a child of the abstract base class OptionBase) that stores an option name (in the form someoption=) and the value belonging to that option. The value is...
7
by: whatluo | last post by:
Hi, all I'm now working on a program which will convert dec number to hex and oct and bin respectively, I've checked the clc but with no luck, so can anybody give me a hit how to make this done...
3
by: Convert TextBox.Text to Int32 Problem | last post by:
Need a little help here. I saw some related posts, so here goes... I have some textboxes which are designed for the user to enter a integer value. In "old school C" we just used the atoi function...
7
by: patang | last post by:
I want to convert amount to words. Is there any funciton available? Example: $230.30 Two Hundred Thirty Dollars and 30/100
4
by: Edwin Knoppert | last post by:
In my code i use the text from a textbox and convert it to a double value. I was using Convert.ToDouble() but i'm used to convert comma to dot. This way i can assure the text is correct. However...
1
by: johnlim20088 | last post by:
Hi, Currently I have 6 web projects located in Visual Source Safe 6.0, as usual, everytime I will open solution file located in my local computer, connected to source safe, then check out/check in...
6
by: Ken Fine | last post by:
This is a basic question. What is the difference between casting and using the Convert.ToXXX methods, from the standpoint of the compiler, in terms of performance, and in other ways? e.g. ...
0
Debadatta Mishra
by: Debadatta Mishra | last post by:
Introduction In this article I will provide you an approach to manipulate an image file. This article gives you an insight into some tricks in java so that you can conceal sensitive information...
0
by: DolphinDB | last post by:
Tired of spending countless mintues downsampling your data? Look no further! In this article, you’ll learn how to efficiently downsample 6.48 billion high-frequency records to 61 million...
0
isladogs
by: isladogs | last post by:
The next Access Europe meeting will be on Wednesday 6 Mar 2024 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM). In this month's session, we are pleased to welcome back...
1
isladogs
by: isladogs | last post by:
The next Access Europe meeting will be on Wednesday 6 Mar 2024 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM). In this month's session, we are pleased to welcome back...
0
by: jfyes | last post by:
As a hardware engineer, after seeing that CEIWEI recently released a new tool for Modbus RTU Over TCP/UDP filtering and monitoring, I actively went to its official website to take a look. It turned...
0
by: ArrayDB | last post by:
The error message I've encountered is; ERROR:root:Error generating model response: exception: access violation writing 0x0000000000005140, which seems to be indicative of an access violation...
1
by: PapaRatzi | last post by:
Hello, I am teaching myself MS Access forms design and Visual Basic. I've created a table to capture a list of Top 30 singles and forms to capture new entries. The final step is a form (unbound)...
0
by: Defcon1945 | last post by:
I'm trying to learn Python using Pycharm but import shutil doesn't work
1
by: Shællîpôpï 09 | last post by:
If u are using a keypad phone, how do u turn on JavaScript, to access features like WhatsApp, Facebook, Instagram....
0
by: Faith0G | last post by:
I am starting a new it consulting business and it's been a while since I setup a new website. Is wordpress still the best web based software for hosting a 5 page website? The webpages will be...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.