Connect to MS Access from C/C++/PHP

Again Access... hey Access was a great database.

So if you are using access and you are thinking in how to use it from PHP or from a C/C++ app then you should check 

mdbtools. 

Does it work on iOS, well there is a discussion about at (http://old.nabble.com/Port-libmdb-(mdb-tools)-for-iOS-td34282658.html)  but I think there might be some licensing issues.

If that is the case I would recommend writting your own version of mdbtools, Take a look at https://github.com/brianb/mdbtools/blob/master/HACKING for detail info about the file format.

Connect to MS Access from C/C++/PHP

Again Access... hey Access was a great database.

So if you are using access and you are thinking in how to use it from PHP or from a C/C++ app then you should check 

mdbtools. 

Does it work on iOS, well there is a discussion about at (http://old.nabble.com/Port-libmdb-(mdb-tools)-for-iOS-td34282658.html)  but I think there might be some licensing issues.

If that is the case I would recommend writting your own version of mdbtools, Take a look at https://github.com/brianb/mdbtools/blob/master/HACKING for detail info about the file format.

Connect to MS Access from Java

This is not an scenario that I commonly find, but now with Android and with the spread of Linux base environments an devices you are just don't want to be limited to just one technology.

So I found this library which I found extremely useful and I can recommend: Jackcess

The following are some code samples from the Jackcess library

• Displaying the contents of a table:

  System.out.println(Database.open(new File("my.mdb")).getTable("MyTable").display());
  

• Iterating through the rows of a table:

  Table table = Database.open(new File("my.mdb")).getTable("MyTable");
  for(Map<String, Object> row : table) {
    System.out.println("Column 'a' has value: " + row.get("a"));
  }
  

• Searching for a row with a specific column value:

  Map<String, Object> row = Cursor.findRow(table, Collections.singletonMap("a", "foo"));
  if(row != null) {
    System.out.println("Found row where 'a' == 'foo': " + row);
  } else {
    System.out.println("Could not find row where 'a' == 'foo'");
  }
  

• Creating a new table and writing data into it:

  Database db = Database.create(new File("new.mdb"));
  Table newTable = new TableBuilder("NewTable")
    .addColumn(new ColumnBuilder("a")
               .setSQLType(Types.INTEGER)
               .toColumn())
    .addColumn(new ColumnBuilder("b")
               .setSQLType(Types.VARCHAR)
               .toColumn())
    .toTable(db);
  newTable.addRow(1, "foo");
  

• Copying the contents of a JDBC ResultSet (e.g. from an external database) into a new table:

  Database.open(new File("my.mdb")).copyTable("Imported", resultSet);

• Copying the contents of a CSV file into a new table:

  Database.open(new File("my.mdb")).importFile("Imported2", new File("my.csv"), ",");

Remember that if you want to use it android you use some tweaks:

"The following steps will make Jackcess compatible with the Android platform.

• Set the system property "com.healthmarketscience.jackcess.brokenNio=true"
• Set the system property "com.healthmarketscience.jackcess.resourcePath=/res/raw/"
• Copy the *.txt, *.mdb, and *.accdb files from the "com/healthmarketscience/jackcess/" directory in the Jackcess jar to the "/res/raw" Android application directory.
• Before executing any Jackcess code, set the current Thread's context classloader, e.g. "Thread.currentThread().setContextClassLoader(Database.class.getClassLoader())"."

Simplify app deployment in .NET

WPF applications deployment on the browser using XBAP

HTML5 lets you deploy your applications everywhere

Embedding Windows Forms Applications in a WebBrowser using XBAP

In this post I will add references to other pages which do a great work on explaining how to use this approach to host a Windows Forms App inside a WebBrowser. 

The technique described here is a deployment solution to ease distribution of applications modernized from legacy technologies to Windows Forms, maybe using the Artinsoft\Mobilize.NET tools ;) 

NOTE: "This workaround of .NET Winforms to WPF and then hosting it in a browser isn't truly moving a Windows based application to a web based application. e.g. database calls will be made from inside the browser on the users PC to the database, not via the IIS server. Therefore this functionality is most useful if you have connected your Winforms UI to you back-end code using web services, then you can have a somewhat web based application."  

Adam Berent gives step by step instrutions:

http://www.codeproject.com/Articles/31429/Embedding-a-NET-WinForms-Application-in-an-Interne 

 

 

 

 

 

 

Figure 1: Example of Windows Forms applications running inside FireFox browser using an XBAP wrapper.

 

Some details that are missing in this article are related to how to publish the application on IIS, and these can described as: 

1. Create a test Certificate within Visual Studio and sign it against the project.  

The following links provides information on how to sing the xbap with your own certificate. 

http://ahmadreza.com/2011/05/20/how-to-sign-the-xbap-with-your-own-certificate/ 
 

2. Within VS publish the application. 

3. Setup the MIME encoding on the IIS server. See http://msdn.microsoft.com/en-us/library/ms752346.aspx 
 

4. Install the certificate on the Client PCs 

The certificate must be added in the trusted publisher and in the trusted root authority. If this is not done correctly you get the error 'Trust not granted' 

Embedding Windows Forms Applications in a WebBrowser using XBAP

In this post I will add references to other pages which do a great work on explaining how to use this approach to host a Windows Forms App inside a WebBrowser. 

The technique described here is a deployment solution to ease distribution of applications modernized from legacy technologies to Windows Forms, maybe using the Artinsoft\Mobilize.NET tools ;) 

NOTE: "This workaround of .NET Winforms to WPF and then hosting it in a browser isn't truly moving a Windows based application to a web based application. e.g. database calls will be made from inside the browser on the users PC to the database, not via the IIS server. Therefore this functionality is most useful if you have connected your Winforms UI to you back-end code using web services, then you can have a somewhat web based application."  

Adam Berent gives step by step instrutions:

http://www.codeproject.com/Articles/31429/Embedding-a-NET-WinForms-Application-in-an-Interne 

 

 

 

 

 

 

Figure 1: Example of Windows Forms applications running inside FireFox browser using an XBAP wrapper.

 

Some details that are missing in this article are related to how to publish the application on IIS, and these can described as: 

1. Create a test Certificate within Visual Studio and sign it against the project.  

The following links provides information on how to sing the xbap with your own certificate. 

http://ahmadreza.com/2011/05/20/how-to-sign-the-xbap-with-your-own-certificate/ 
 

2. Within VS publish the application. 

3. Setup the MIME encoding on the IIS server. See http://msdn.microsoft.com/en-us/library/ms752346.aspx 
 

4. Install the certificate on the Client PCs 

The certificate must be added in the trusted publisher and in the trusted root authority. If this is not done correctly you get the error 'Trust not granted' 

Silverlight as a mechanism for simplification of application deployment

Embedding Windows Forms Applications directly in a WebBrowser

Figure 1: Example of simple Hello Word Windows Forms App embedded in Browser

Figure 2: Example of a more complex Windows Forms App consuming data from a Web Service

" However before using Windows Forms controls in IE, you need to be aware of the benefits and limitations. The main benefits include: 

•          The ability to deliver dynamic rich user experience through the Web 

•          Automatic caching of compiled code on the client 

•          Seamless integration with .NET Code Access Security that allows you to leverage the .NET security model from within the client side 

•          Improved performance over Java applets 

•           It requires Windows operating system on the client side 

•           Internet Explorer 6.0-9.0 is the only browser that provides support for this type of hosting 

•           It requires .NET runtime to be installed on the client machine. 

•           It also requires Windows 2000 and IIS 5.0 or above on the server side" 

  
  

The obscure way to open an Access 97 database with MDW Security in Access2010

I was in an AccessMigration to SQL Server and i needed to open an Access97 database with security (using a system.mdw file).

It took me a while to do, but it is possible to open an Access97 Database in Access2010.

I really thing that it is a little obscure. But these are the steps:

1. First open Access2010

2. After Opening Access2010, press Ctrl + G. That will open the Microsoft Visual Basic for Applications window.

3. On the Immediate Window run this command (to run it just time the command and press Enter): DoCmd.RunCommand acCmdWorkgroupAdministrator

4. Once you run this command you will see a dialog with a title of Workgroup Administrator, press the Join Button

5. When you press the join Button a Dialog with Title Workgroup Information File will prompt Click Browse and find your System.mdw file and press OK. And press Ok on the Workgroup Administrator Dialog

6. Now close Access 2010

7. Open Windows explorer. Find your .mdb file and double click it. Access2010 will prompt for user/password and then will upgrade your database.

Migrating the CommonDialog print dialog

In VB6 you could use the commondialog to show several of the 
standard operating system dialogs. For example show the a 
the print setup dialog box or the print dialog box.

VB6 Example showing the Print Setup Dialog Box

cdlgprint.Flags = cdlPDPrintSetup

    cdlgprint.ShowPrinter

In .NET you have 4 kinds of Priting Dialogs:

PageSetupDialog

PrintDialog

PrintDocument

PrintPreviewDialog

So during a migration remember that if your were using the the CommonDialog.Flags 

property to show the PrintSetupDialog you will have to change that for something like

var cdlgprint_ForPrintSetup  = new PrintSetupDialog();

 cdlgprint_ForPrintSetup.Print()

BEWARE of FileSystem.FilePutObject

When you are migrating from VB6 to VB.NET most of the Put statements will be migrated to 

FileSystem.FilePutObject http://msdn.microsoft.com/en-us/library/z07he9as.aspx

The problem with this is that if you need that the files generated by your application to be compatible byte per byte
with your VB6 generated files you must put special attention.

Take a look at this example: 

Module Module1

    Sub Main()
              Dim str = "TEXTDATA"
              FileSystem.FileOpen(1, "c:\temp\file1.dat", OpenMode.Random, OpenAccess.Write, , 30)
              FileSystem.FilePutObject(1, str, 2)
              FileSystem.FileClose(1)
    End Sub

End Module

Module Module1

    Sub Main()
              Dim str = "TEXTDATA TEXTDATA TEXTDATA"
              FileSystem.FileOpen(1, "c:\temp\file1.dat", OpenMode.Random, OpenAccess.Write, , 30)
              FileSystem.FilePut(1, str, 2)
              FileSystem.FileClose(1)
    End Sub

End Module

The difference might seem minimal but it can be hard to detect.

The different byte is caused by using the FilePutObject instead of FilePut method

VB6 Migration, HTML5 Forms and ASP.NET Web Forms

VB6 Migration, HTML5 Forms and ASP.NET Web Forms

If you come from a VB6 background, and your application is still in VB6,
you are probably wondering that this might be a good time to move out of VB6.

But is also a complex time. Which is right path: WinForms, Silverlight, WPF, HTML5?

Choosing the right target platform can be very tricky and depends on many varaiables.
So let's assume in this post that you have already decided that you want to use Web Tecnologies
and why not HTML5 as well.

ASP.NET Web Forms is a good technologie and developing forms with it is also very easy,
but can you develop HTML5 applications with this?

Well Brandon Satrom has a nice column in MSDN Magazine about Web Forms with HTML5 Forms.
He says:

If you’re planning to do HTML5 Forms development with ASP.NET Web Forms, there’s good news:
Many HTML5-related updates to .NET and Visual Studio are being released out-of-band, so you
don’t have to wait for the next framework version to use these features today.

To get started with HTML5 Forms and ASP.NET Web Forms, you’ll need to grab a couple of updates.
 First, make sure you have Visual Studio 2010 SP1 (bit.ly/nQzsld).
In addition to adding support for new HTML5 input types and attributes, the service pack also
provides some updates that enable you to use the new HTML5 input types on the TextBox server control.
Without this update, you’d see compile-time errors when using the new types.

You’ll also want to grab the Microsoft .NET Framework 4 Reliability Update 1 (bit.ly/qOG7Ni).
This update is designed to fix a handful of problems related to using the new HTML5 input types
with ASP.NET Web Forms. Scott Hunter covers a few of those—UpdatePanel, Validation Controls
and Callbacks—in a blog post from early August that you can check out at bit.ly/qE7jLz.

Update:

Mobilize.NET and Artinsoft.com company now helps in the HTML5 migration problem from VB6, Windows Forms and PowerBuilder. http://mobilize.net/default.aspx

Migrating Access to SQL Server

If during a VB6 migration you decide o take a step forward and move your databases to MS SQL

don't worry. The SQL Server team has a tool just for that.

I just don't know why it is so hard to find it in google. But the appropiate link is:

http://blogs.msdn.com/b/ssma/p/access.aspx

Also a recent article in Teched goes into all the gory details: http://technet.microsoft.com/en-us/magazine/hh334645.aspx

Good Luck and don't hesitate to contact us for any doubts.

Running Object Table and .NET

What is the ROT?

“Using ROT (Running Object Table) is a great way to establish interprocess communication between two windows applications. From a purely logical aspect, one application registers a pointer to an instance of a class in the ROT, the other one gets a pointer pointing to the same instance of the registered class and therefore can use the same instance of the class via this pointer. The class that is registered has to be a COM class, otherwise it can be written in any language. The application that will retrieve the pointer from the ROT can be written in any language that can use COM, as ROT gives a pointer to a COM interface.”

Can it be implemented in .NET?

Sure a .NET application can be exposed thru COM and then its pointer can be gotten and consumed by other applications querying the ROT.

And excelent example can be found here: http://www.codeproject.com/KB/COM/ROTStuff.aspx

As always it has its caveats. Be careful.

Obvious replacement?

Well if what you want is (Interprocess Communication) IPC,there are several options in .NET :

* Classical .NET remoting which is very simple and stable to

* Named Pipes see an example here http://bartdesmet.net/blogs/bart/archive/2007/04/12/getting-started-with-named-pipes.aspx

* or WCF with Named Pipes, an example here http://www.codeproject.com/KB/WCF/WCF_CommOptions_part1.aspx

WCF can be an interesting option specially if we were doing things like DCOM and Remote monikers.

Ohhh Glorious Silverlight Theming!!

I’m very fond of one of our newest products www.silverlightmigration.com 

It provides a way to refresh your applications to take full advantage of XAML,
solves deployment issues, runs in Windows, Mac OSX and in some Linux with
MoonLight

And we are event tuning it up for the next jump: Windows 8… keep tuned for that.

One of the things a like most about this solution is XAML theming.

In general there are good themes but today I would like to recommend the SystemColors theme
from http://blogs.msdn.com/b/corrinab/archive/2010/04/12/9994045.aspx

You can download it from here.
This theme allows you to style all core, sdk and toolkit controls so they will use the theme that
you currently have in Windows. These might be very useful for some LOB applications,
so the applications can see more like native applications, and with the advent of Silverlight 5 and more
native integration, better Out-of-Browser execution I think it is just fine.

See some screen shots:

A very large .VBP - Visual Basic 6.0 project for those who are only familiar with the .vbproj extension :)

I just came back from executing a Ready assessment for a company in Minnesota, where I analyzed 740,000 lines of code in a VB6 application, of which 660,000 belonged to a single Visual Basic project (.vbp).  This is actually the largest single .vbp I have seen so far, beating the previous record of about 500,000 lines of code held by an European company.  We have migrated plenty of applications that contain 1+ million lines of code, but they are usually distributed across many .vbp’s.

Though unusual, single vbp’s of this size are perfectly manageable from a migration standpoint, and here are some things that can be done to deal with them:

• Ensure that the migration computer has at the very minimum, 3GB of RAM. 
• Look for customization opportunities before you start migrating the code.  Customizing the VBUC for this specific VBP can reduce manual effort drastically.
• When making manual changes, start with a small team until you get the project to compile, especially if migrating to VB.NET as the compiler has a maximum of build errors that it can show at any given time. 
• Once the application compiles, increase the team size and go for Visual Equivalence by distributing the different forms and user controls across your developers.

Dealing with Crystal Reports

Crystal Reports was one of the most popular reporting engines in VB6, and still holds a strong market presence with its .NET version.  However, the object model in the .NET version of Crystal has changed so dramatically from the VB6 days that automating this conversion is not be cost-effective in most cases.  These are the options when dealing with Crystal Reports in an application to be migrated to .NET:

• Use COM Interop: we have successfully migrated many applications with Crystal Reports through COM Interop.  However, this only works when the report objects are populated using Crystal’s own querying engine (for example, sending a SQL string to Crystal so it can retrieve the data directly from the database), instead of providing an already-populated RecordSet as a data source for the report.  This is because once the application is ported to .NET, its RecordSets will become ADO.NET DataSets (or Helper Classes inheriting from DataSet), which will not be compatible with the legacy version of Crystal.  This can be fixed this by disabling the conversion of ADO to ADO.NET, but this is not desirable in most enterprise applications, and may compromise future maintainability and enhancements.

• Replace with Crystal .NET or another .NET-compatible reporting engine: this is also a popular option among our clients, as it removes the legacy Crystal component.  On the other hand, this replacement is manual and will require adjustments to the report layout, if converting to the .NET version of Crystal, or even a rewrite of the reports if migrating to other engines.

More on iOS / XCode / Objective-C Migration Methods and Multiple Parameters to C#

On a previous post I was describing how some basic Objective-C elements were mapped to C#.
In particular I showed how the @interface and @implementation definitions are to be mapped in .Net, including basic properties.
In this post I will show a little about how methods are migrated.

There are several things to analyze when moving Objective-C code to C# it might be simple but can be a complicated
task. Objective-C is a language created under the inspiration of SmallTalk. And in Smalltalk programmer do not think of
method calls but instead of message sending and that is something to keep in mind when doing this migration.
Also all methods are virtual and even if there are access restriction in Objective-C I will map those methods to
public for simplicity sake.

In the previous post we had:

FIRSTFIRST

Fraction.h

#import <Foundation/NSObject.h>
@interface Fraction: NSObject {
    int numerator;
    int denominator;
}
-(void) print;
-(void) setNumerator: (int) n;
-(void) setDenominator: (int) d;
-(int) numerator;
-(int) denominator;
@end

And

Fraction.m

#import "Fraction.h"
#import <stdio.h>

@implementation Fraction
-(void) print {
    printf( "%i/%i", numerator, denominator );
}

-(void) setNumerator: (int) n {
    numerator = n;
}

-(void) setDenominator: (int) d {
    denominator = d;
}

-(int) denominator {
    return denominator;
}

-(int) numerator {
    return numerator;
}
@end

And that example shows properties and methods with no parameter. OK. Now lets just focus on methods with 0, 1 and more parameters.

MethodsExample.h

#import <Foundation/NSObject.h>
@interface MethodsExample: NSObject {

}
-(void) print;

-(int) multiplyByTwo: (int) n ;

-(void) multiplyTwoNumers: (int) a andSecondNumber: b;

@end

MethodsExample.m

#import "MethodsExample.h"
#import <stdio.h>

@implementation MethodsExample
-(void) print {
    printf( "Hola mundo\n" );
}

-(int) multiplyByTwo: (int) n {
    return n * 2;
}

-(int) multiplyTwoNumbers: (int) a  andSecondNumber (int) b {
    return a * b;
}
@end

And calling those functions will be:

#import <stdio.h>
#import "MethodsExample.h"

int main( int argc, const char *argv[] ) {
    // create a new instance
    MethodsExample *m = [[MethodsExample alloc] init];
    [m print]; 
    int result;
    result = [m multiplyByTwo: 1];
    result = [m multiplyTwoNumbers: 1 andSecondNumber: 5];
    // free memory
    [m release];
    return 0;
}

This little example shows some of the particularities of Objective-C. 
In Objetive-C all parameters starting from the second parameter can have 
what is called a label and labels are similar to namedParameter. Ok lets go ahead and map that class.

using System;

public class MethodsExample
{
    public virtual print() {
        Console.WriteLine("Hola mundo\n");
    }
    public virtual int multiplyByTwo(int n)
    {
      return n * 2;
    }
    //AproachOne
    public virtual int multiplyTwoNumber(int a,int andSecondNumber)
    {
        return a * andSecondNumber;
    }
    //AproachTwo
    //I just renamed as multiplyTwoNumber2 to avoid compilation errors.
    //The idea is that you will choose one of the two aproaches
    //or define a criteria for the instances where aproach one should be used
    //instead of approach two
    public virtual int multiplyTwoNumber(int a,int andSecondNumber)
    {
        int n = andSecondNumber;
        //This aproach will be better if you have a lot of code in the method
        //and you prefer to keep the original arg name
        return a * n;
    }

}

So the thing here is what to use as the parameter name, the label or the argument name. 
In the example you can see the two approaches in the multiplyTwoNumbers case.

 And calling the methods is simple and the named parameters syntax can be exploited.

using System;

public static class Program
{
    public static int Main(string[] argv ) {
        // create a new instance
        var m = new MethodsExample();
        m.print();
        int result;
        result = m.multiplyByTwo(1);
        result = m.multiplyTwoNumbers(1,andSecondNumber: 5); //using named parameters
        // free memory
        m.release();
        return 0;
    }
}

REMEMBER: This is just a glimpse of some mapping concepts from Objective-C to C#. 
There are many subtle details in this kind of migration and is my belief that only
an automated tool is able to process all those details in an effectively and more error-free
than a manual approach. For example in objective-c if m is null that will not cause any error if you
do something like [m print] and in C# that will throw an error. However a migration tool could determine
if the variable will have a value before its use and avoid adding unnecessary if (m!=null) statements.

We will examine this and other details in following posts. I hope this little examples give you enough information

for playing around migrating some Objective-C code. And if it gets too complicated just send me an email!!!