Dataset save columns as Attributes

This code is so handy that I'm posting it just to remember. I preffer to serialize my datasets as attributes instead of elements. And its just a matter of using a setting. See: 

Dim cnPubs As New SqlConnection("Data Source=<servername>;user id=<username>;" & _
                                "password=<password>;Initial Catalog=Pubs;")
Dim daAuthors As New SqlDataAdapter("Select * from Authors", cnPubs)

Dim ds As New DataSet()
cnPubs.Open()
daAuthors.Fill(ds, "Authors")

Dim dc As DataColumn
For Each dc In ds.Tables("Authors").Columns
        dc.ColumnMapping = MappingType.Attribute
Next

ds.WriteXml("c:\Authors.xml")

Console.WriteLine("Completed writing XML file, using a DataSet")
Console.Read()

ActiveX Controls in .NET and the Enabled bug

We found and interesting bug during a migration. The issue was that when there was an iteration through the controls in the forms, and you set the Enabled property, the property didn't get set.

After some research my friend Olman found this workaroung

foreach(Control c in Controls)
{ 
  ctrl.Enabled = true;
  if (ctrl is AxHost) ((AxHost)ctrl).Enabled = true;
}

Install Assembly in GAC with C#

Do you want to create a program to install your assembly in the GAC using C#. Well if you had that requirement or you are just curious, here is how.

I read these three articles:

Demystifying the .NET Global Assembly Cache

GAC API Interface 

Undocumented Fusion

What I wanted just a straight answer of how to do it. Well here is how:

using System;

using System.Collections.Generic;

using System.Text;

using System.GAC;

//// Artinsoft

//// Author: Mauricio Rojas orellabac@gmail.com mrojas@artinsoft.com

//// This program uses the undocumented GAC API to perform a simple install of an assembly in the GAC

namespace AddAssemblyToGAC

{

    class Program

    {

        static void Main(string[] args)

        {

            // Create an FUSION_INSTALL_REFERENCE struct and fill it with data

            FUSION_INSTALL_REFERENCE[] installReference = new FUSION_INSTALL_REFERENCE[1];

            installReference[0].dwFlags = 0;

            // Using opaque scheme here

            installReference[0].guidScheme = System.GAC.AssemblyCache.FUSION_REFCOUNT_OPAQUE_STRING_GUID;

            installReference[0].szIdentifier = "My Pretty Aplication Identifier";

            installReference[0].szNonCannonicalData= "My other info";

            // Get an IAssemblyCache interface

            IAssemblyCache pCache = AssemblyCache.CreateAssemblyCache();

            String AssemblyFilePath = args[0];

            if (!System.IO.File.Exists(AssemblyFilePath))

            {

                Console.WriteLine("Hey! Please use a valid path to an assembly, assembly was not found!");

            }

            int result = pCache.InstallAssembly(0, AssemblyFilePath,installReference);

            //NOTE recently someone reported a problem with this code and I tried this:

            // int result = pCache.InstallAssembly(0, AssemblyFilePath,null); and it worked. I think is a marshalling issue I will probably review it later

            Console.WriteLine("Process returned " + result);

            Console.WriteLine("Done!");

        }

    }

}

And here's the complete source code for this application: DOWNLOAD SOURCE CODE AND BINARIES

Useful MSBuild Custom Tasks

I present here the implementation of some useful tasks
In Artinsoft we perform massive migrations of VB6 code to VB.Net
and C#.

And sometimes after migration there are customizations to be
performed on the code, to add new functionality or to set certain new
properties.

 The idea was to provide a couple of very simple and puntual MSBuildTask
 to illustrate how easy it is to create custom tasks and to provide a starting
 point to create new one.

 You can freely use this code, just keep this comments and remember this is just
 a sample code. There are not warranties. ;) And i made it a rush I know it could have
 been written better

 Artinsoft
 mrojas@artinsoft.com
 

The implemented tasks are:

RemoveCOMReference 

FixOutputPath 

The following is a sample project file

<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">

<!-- make sure that the Assembly is in a place where msbuild can find it, a simple way is just to put it 

in the same directory of your .proj file -->

<UsingTask TaskName="SomeUsefulTasks.MSBuild.RemoveCOMReference"    
  AssemblyFile="SomeUsefulTasks.dll"/> 

<UsingTask TaskName="SomeUsefulTasks.MSBuild.FixOutputPath"         
  AssemblyFile="SomeUsefulTasks.dll"/> 

<UsingTask TaskName="SomeUsefulTasks.MSBuild.AddProjectReference"   
  AssemblyFile="SomeUsefulTasks.dll"/> 

<UsingTask TaskName="SomeUsefulTasks.MSBuild.AddSimpleReference"    
  AssemblyFile="SomeUsefulTasks.dll"/> 

<UsingTask TaskName="SomeUsefulTasks.MSBuild.ChangeProjectBuildSetting"    
  AssemblyFile="SomeUsefulTasks.dll"/> 

   <ItemGroup>

    <VSProjects Include="$(Start)\**\*.*proj" />

  </ItemGroup>

<!--

Run with 
MSBUILD SampleProject.proj /target:COMReference /p:Start="C:\MyCode"

-->

  <Target Name="COMReference">

    <RemoveCOMReference SourceFiles="@(VSProjects)" ComReferenceName="MSXML2" />

  </Target> 

<!-- 

Adds a project reference  

Run with 

MSBUILD SampleProject.proj /target:AddProjectReference /p:Start="C:\MyCode" /p:ProjectPath="C:\MyCode\MyNewSuperProject\Project1.csproj"

-->

   <Target Name="AddProjectReference">

      <AddProjectReference SourceFiles="@(VSProjects)"  AbsolutePathToProject="$(ProjectPath)"/>

   </Target> 

<!-- 
Adds a reference to a standard assembly 

Run with 

MSBUILD SampleProject.proj /target:AddSimpleReference /p:Start="C:\MyCode" /p:Reference="System.EnterpriseServices"   

-->

<Target Name="AddSimpleReference">

      <AddSimpleReference SourceFiles="@(VSProjects)" Reference="$(Reference)" />

</Target> 

<!-- 
Resets the OutputPaths to .\bin\Debug and .\bin\Release 

Run with 

MSBUILD SampleProject.proj /target:FixOutput /p:Start="C:\MyCode" /p:Reference="System.EnterpriseServices"   

-->

<Target Name="FixOutput">

    <FixOutputPath SourceFiles="@(VSProjects)"  />

</Target> 

<!-- 

Adds a reference to a standard assembly 

There are several options here for example to set the project debug info to pdb-only do this:

Run with 

MSBUILD SampleProject.proj /target:ChangeSettingToPDBOnly /p:Start="C:\MyCode" 

Or run with 

MSBUILD SampleProject.proj /target:ChangeSettingAddAConstant /p:Start="C:\MyCode" 

Or run with 

MSBUILD SampleProject.proj /target:SettingComInterop /p:Start="C:\MyCode" 

-->

<Target Name="ChangeSettingToPDBOnly">

      <ChangeProjectBuildSetting 

          SourceFiles="@(VSProjects)" 

          ConfigurationType="All" 

          Setting="DebugType" 

          NewValue="pdbonly" />

</Target> 

<Target Name="ChangeSettingAddAConstant">

      <ChangeProjectBuildSetting 

          SourceFiles="@(VSProjects)" 

          ConfigurationType="All" 

          Setting="DefineConstants" 

          NewValue="MYNEWVAL" 

          Add="True"/>

</Target> 

<Target Name="SettingComInterop">

      <ChangeProjectBuildSetting 

          SourceFiles="@(VSProjects)" 

          ConfigurationType="All" 

          Setting="RegisterForComInterop" 

         NewValue="true" />

</Target> 

</Project>

DOWNLOAD CODE AND BINARIES

ActiveX exceptions when running in .NET

During migration to C# or .NET it is easier to keep the same ActiveX.
The VBCompanion does a great work in migrating the ActiveX control using the .NET ActiveX wrappings and fixing all method calls. 
Sadly sometimes those ActiveX do not work properly in .NET.

Well we have good news.
Recently my friend Jose David (who we keep bothering because he is now 
a Project Manager and now he only programs in MS Excel and MS Project, I added the MS by his request :P) fixed a curious bug
we had with an aplication we migrated from VB6 to C#.

The thing is that the aplication had an ActiveX control with a strange runtime behaviour.
We migrated the application keeping the ActiveX control and in most ocasions it worked ok.

But randomly it started throwing exceptions.

During the testing he discovered that if he repeated the steps slowly the bug did not reproduced.

So his idea was that it was due a garbage collection issue. And SURPRINSINLY he was right :P

He added this:

System.GC.Collect();

System.

GC.WaitForPendingFinalizers();

 And the application started to work.

It seems like some of the COM objects needed a little more time for releasing all references :)

IsMissing migration in VB.NET or C#

Recently  we added some support for migrating the IsMissing function to VB.NEt or C#

The thing is. In VB6 the IsMissing Function is TRUE only if you have something like:

Public Sub Foo(Optional str)

Where you dont specify the variable type, or if you have

Public Sub Foo(Optional str as Variant)

And is IsMissing is FALSE for any other case. Including Optional variables whose definition type is not Variant.

So let's see some examples to illustrate the idea:
 Example 1:

Public Sub Foo(str, a As Integer, b As Integer, Optional c As Integer)
    MsgBox (str & "Foo Is missing a " & IsMissing(a))
    MsgBox (str & "Foo Is missing b " & IsMissing(b))
    MsgBox (str & "Foo Is missing c " & IsMissing(c))
End Sub

It occurs that IsMissing is really FALSE in all cases. So it is equivalent to:

Public Sub Foo(str, a As Integer, b As Integer, Optional c As Integer)
    MsgBox (str & "Foo Is missing a " & false)
    MsgBox (str & "Foo Is missing b " & false)
    MsgBox (str & "Foo Is missing c " & false)
End Sub

Example 2:

Public Sub Goo(str, a As Integer, b As Integer, Optional c As Object, Optional d As Byte, Optional e)
    MsgBox (str & "Goo Is missing a" & IsMissing(a))
    MsgBox (str & "Goo Is missing b" & IsMissing(b))
    MsgBox (str & "Goo Is missing c" & IsMissing(c))
    MsgBox (str & "Goo Is missing d" & IsMissing(d))
    MsgBox (str & "Goo Is missing e" & IsMissing(e))
End Sub

All cases EXCEPT "e" are equivalent to FALSE

Public Sub Goo(str, a As Integer, b As Integer, Optional c As Object, Optional d As Byte, Optional e)
    MsgBox (str & "Goo Is missing a" & false)
    MsgBox (str & "Goo Is missing b" & false)
    MsgBox (str & "Goo Is missing c" &false)
    MsgBox (str & "Goo Is missing d" & false)
    MsgBox (str & "Goo Is missing e" & IsMissing(e))
End Sub

So if you are migrating your VB6 Code to C# put attention to these little details it can save you a lot of time.And remember that this is just one feature of VBCompanion tool ;)

Case Sensitive SQL Server

The only thing wrong was the the case. For example he had COLUMN1 instead of Column1. I had never seen that problem in SQLServer.
I had seed that in Sybase but not in SQLServer. He solved that by changing the database collating sequence to something like this:

alter database database1 collate SQL_Latin1_General_CP1_CI_AI

the CI in the collating indicates Case Insensitive

For more information on SQL Server collations check: http://msdn2.microsoft.com/en-us/library/aa258233(SQL.80).aspx

And you determine your current database collation use a code like this: