ADODB RecordSet Save in C# ASP.NET

9. October 2008 04:10 by Mrojas in General  //  Tags: , , ,   //   Comments (0)

I saw this with Francisco and this is one possible solution:

ASP Source

rs.Save Response, adPersistXML

rs is an ADODB.RecordSet variable, and its result is being written to the ASP Response

Wrong Migration

rs.Save(Response <-- The ASP.NET Response is not COM, ADODB.Recordset is a COM object, ADODB.PersistFormatEnum.adPersistXML);  

 So we cannot write directly to the ASP.NET response. We need a COM Stream object

Solution

ADODB.Stream s = new ADODB.Stream();

rs.Save(s, ADODB.PersistFormatEnum.adPersistXML);               

Response.Write(s.ReadText(-1));

In this example an ADODB.Stream object is created, data is written into it and the it is flushed to the ASP.NET response

Vb Migration (not for the weak of mind) Post 2

14. August 2008 05:50 by Mrojas in General  //  Tags: , , , ,   //   Comments (0)

When people decide to migrate their VB6 applications they eventually end up questioning where they should go. Is VB.NET or C# a good choice?

I have my personal preference, but my emphasis is in developing the technology to take where YOU want to go.

VB.NET is a VB dialect very similar to VB6. It supports several constructs and it makes the changes easier.
C# has several differences from VB6, but it has it a growing language with lots of enthusiasts in its community.
Obviously migrating VB6 to VB dialect is a task far more easier than migrating to a different language.
However we are a research company with years of work in this area and challenges is just what we love.

Let's use a methaphor here.

My beautiful wife, was born in Moscow, Russia. Like her, I really enjoy reading a good book. Some of my favorite authors are
russian authors like Dostoievsky, Tolstoi and Chejov. However I still do not speak russian. I have tried, and I will keep trying but
I still don't know russian. I have read only translations of their books, and I really enjoy them.
As a native speaker my wife always tells me, that it is not the same to read those books in another language besides russian.
And they are phrases (specially in Chejov books that I might not completely understand) but I really got the author
message and enjoyed it.
Translating a book from russian to a more similar language like Ucranian is easier than translating it to English or Spanish.
But I think everybody agrees that is a task than can be done.

You can use terrible works case scenarios, but these scenarios must be analized.
Let see (I took these example from the link in that Francesco put in my previous post http://blogs.artinsoft.net/mrojas/archive/2008/08/07/vb-migration-not-for-the-weak-of-mind.aspx)

If you have code like this:

Sub CopyFiles(ByVal throwIfError As Boolean)
    If Not throwIfError Then On Error Resume Next
    Dim fso As New FileSystemObject
    fso.CopyFile "sourcefile1", "destfile1"
    fso.CopyFile "sourcefile2", "destfile2"
    fso.CopyFile "sourcefile3", "destfile3"
    ' seven more CopyFile method calls …
End Sub


and you translate it to:

void CopyFiles(bool throwIfError)
{
    Scripting.FileSystemObject fso = new Scripting.FileSystemObjectClass();
    try
    {
        fso.CopyFile("sourcefile1", "destfile1", true);
    }
    catch
    {
        if (throwIfError)
        {
            throw;
        }
    }
    try
    {
        fso.CopyFile("sourcefile1", "destfile1", true);
    }
    catch
    {
        if (throwIfError)
        {
            throw;
        }
    }
    try
    {
        fso.CopyFile("sourcefile1", "destfile1", true);
    }
    catch
    {
        if (throwIfError)
        {
            throw;
        }
    }
    // seven more try-catch blocks
}

I think that the russian is really keep in this translation.

First of all. When you do a translation, you should try to make it as native as possible. So why will you keep using a COM function when there is an
equivalent in .NET. So why not use System.IO.File.CopyFile("sourcefile1", "destfile1", true); instead?

Second of all. The On Error Resume Next, I agree is a not a natural statement in C#. I really think that using it could provide results that are less predictable.
Why? Becuase after executing it, are you sure that all the CopyFile occurred successfully? I would prefer wrapping the whole code inside a try-catch instead of trying
to provide an implementation that is not natural in C#, will Aspect Oriented programming provide a clean solution for this cases. Maybe?

RPG and COBOL to Object Oriented Programming, PowerBuilder to C#, Hierarquical Databases to Relational Databases are just the kind of challenges we have faced in our research project.
Not everything is easy, and we might not be able to automate all the tasks (commonly due to the cost of implementing the automation not becuase of feasability).

But at the end Could you understand the whole novel?, even if you didn't understand the joke in the one of the paragraphs in the page?

My years of reading make be belive that you can.


 

VB Migration (not for the weak of mind)

7. August 2008 05:14 by Mrojas in General  //  Tags: , , , ,   //   Comments (0)

Motivation: 

I hate to be disappointed. Specially if it is by a person you had respect for. And that's exactly what Francisco Balena from VB Migration Partner, has done. I have respected him for his books and all his VB6 experience. In terms of legacy VB6 code he is a monster. He is the man.

But in terms of code migration...

I'm not saying this because I work on code migration or maybe I'm biased a little by the fact that I work almost 10 years with a company that has done source code migration research on a big number of legacy languages such as COBOL, RPG, PL\1, Algol, Progress, PowerBuilder and also VB6.

I can tell the difference between a "compiler" and a system that rewrites a expression to the closest equivalent in the target language. We are aware of limitations. We are aware of paradigm differences and functional equivalence, but we talk from experience. We talk about our results. And we have proven those things we talk about.

 Let's says you create a Cobol Library with a "MOVE" function, and a COBOLPicture Type and add minus, divide, and add operators. And I write something like:

CobolPicture x = new CobolPicture("XXXX");

x.move(10);

x.add(10);

We have things like that, and it works. It's feasible and maybe there are cases where that is a solution. But we are also proud of have researchers that have been able to detect pattern to rewrite something like that like:

int x = 0;

x = 10;

x+=10;

And saying, that something is not possible just because you can't or you dont like it, just seem uneducated to me.

 All of this has motivated me to start a series of chapters I for a small blog book I will call VB Migration (not for the weak of mind).

For those of you, who really are tecnology savvy and are in the process of a VB Migration, this is YOUR book.

Debugging AJAX

12. December 2007 05:00 by Mrojas in General  //  Tags: , , ,   //   Comments (0)
AJAX applications are great
Their coolness factor is high, and your clients
will be trilled by the new interactivity of your pages
But as a developer when you have a problem with
AJAX it could be hard to track. Because there is
a lot going on behind the scenes
Some of our costumers migrate their ASP applications to
to ASP.NET and it's natural that they want
some AJAX in it.
So I found a GREAT GREAT application for AJAX debugging
It's called fiddler. I cannot describe it all for you so go its site and watch the videos
The tool is just amazing :)
It really can see everything that the browser
receives and sends and more.
A definitive must Fiddler

Localize your VB apps

28. May 2007 06:45 by Mrojas in General  //  Tags: , , ,   //   Comments (0)
Localize a VB6 application can be cumbersome, specially if it was not even originally planned to be localized.
Nowadays is common that you're clients might demand support for different languages.
While a localization task is still difficult, we have found excellent results performing it during a VB Migration.
Our tools allow us to easily externalize all your strings. After that the traslation task becomes easy, and you can even use the help
of nice projets like Automatically Translate your .NET resource files with Google Translate

ASP to ASP.NET: File exists

31. December 2006 07:30 by Mrojas in General  //  Tags:   //   Comments (0)


This is the migration of a snippet of ASP classic to ASP.Net

 

Checking that a File Exists ASP Classic

<%
Dim strExists  
Dim strNotExists 
Dim objFileSystemObjectVar
``
strExists    = "exists.txt"
strNotExists = "error.txt"
 
Set objFileSystemObjectVar = Server.CreateObject("Scripting.FileSystemObject")
 
' The FileExists method expects a fully qualified path and
' use Server.MapPath 
%>
<p>
&quot;<%= strExists %>&quot; exists:
<b><%=objFileSystemObjectVar.FileExists(Server.MapPath(strExists)) %></b>
</p>
<p>
&quot;<%= strNotExists %>&quot; exists:
<b><%= objFileSystemObjectVar.FileExists(Server.MapPath(strNotExists)) %></b>
</p>

 

Checking that a file exists ASP.NET

 

<%@ Page Language="VB" %>
<%@ Import Namespace="System.IO" %>
<script language="VB" runat="server">
        Dim strExists As String = "exists.txt"
        Dim strNotExists As String = "error.txt"
</script>
<p>
&quot;<%= strExists %>&quot; exists:
<b><%=File.Exists(Server.MapPath(strExists))%></b>
</p>
<p>
&quot;<%= strNotExists %>&quot; exists:
<b><%= File.Exists(Server.MapPath(strNotExists))%></b>
</p>