Develop Reference

Unity SQLite local database

I am making a small game in Unity and I'm in need of a database. I tried using SQLite database because that seemed to be recommended by the web.
Now I'm having troubles with actually connecting to the local database via c#.
I implemented the Data in SQLite .dll's.
I am trying to get 1 name from the database that I created using SQLite developer.
Below is my DataConnection class, which I use to connect to the database.
using UnityEngine;
using System.Collections;
using System.Data;
using Mono.Data.SqliteClient;
public class Dataconnection : MonoBehaviour {
private string _constr = #"Data Source=C:\Program Files (x86)\SharpPlus\SqliteDev\GameDatabase.db;Version=3;";
private IDbConnection _dbc;
private IDbCommand _dbcm;
private IDataReader _dbr;
public Dataconnection()
{
}
public Dataconnection(string constring)
{
_constr = constring;
}
public string ExcecuteQuery(string SQL)
{
string output = "";
try
{
_dbc = new SqliteConnection(_constr);
_dbc.Open();
_dbcm = _dbc.CreateCommand();
_dbcm.CommandText = SQL;
_dbr = _dbcm.ExecuteReader();
}
catch
{
}
while (_dbr.Read())
{
output = _dbr.GetString(0);
}
_dbc.Close();
return output;
}
}
Then I call the following method from another class:
datacon.ExcecuteQuery("SELECT name FROM employee WHERE empid = 1;");
I get the following errors when running the code:
So I'm guessing it has something to do with a 32/64 -bit mismatch or is there something wrong with creating an instance of a script like this?:
private Dataconnection datacon;
void Start()
{
datacon = new Dataconnection();
}
Happy to receive any help at all. I'm familiar with using database, just new to SQLite.

It says it cannot load the native sqlite.dll because you have there 64 bit version and it needs 32 bit
Place this in your app folder https://www.sqlite.org/2015/sqlite-dll-win32-x86-3081001.zip
Please fill that empty catch on line 38 with a throw;
as there is an exception hidden there which is the true cause of the null reference.
You could also post your connection string so I could make this answer better.

I got it working now. The problem was my that one of the SQLite .dll's was still 32bit. I did this tutorial over again and searched google for the 64bit .dll files and now it's working.

get GuiApplication of running Sap logon vb6 to c#

I have to migrate a vb6 program to C# .net 3.5
the user starts SAP logon and authenticates,
then he can use the tool to fetch and insert the data using the tool
the problem:
i can create a new GuiApplication with reflection, but i can't fetch currently opened GuiSessions with it :/
here is the vb6 part of the code that gets currently opened GuiApplication with all opened GuiSessions
Dim obj As Object
Set obj = CreateObject("SAPGUI")
Set obj = obj.GetScriptingEngine
If TypeName(obj) = "GuiApplication" Then
Set SapAutomationObject = obj
SapAutomationObject.AllowSystemMessages = False
Debug.Print "SAP Automation OK"
End If
i tried it with reflection:
GuiApplication Application = (GuiApplication)System.Activator.CreateInstance(Type.GetTypeFromProgID("SapGui.S‌​criptingCtrl.1"));
i got an instance but no existing sessions

public static void testConnection()
{
SapROTWr.CSapROTWrapper sapROTWrapper = new SapROTWr.CSapROTWrapper();
object SapGuilRot = sapROTWrapper.GetROTEntry("SAPGUI");
object engine = SapGuilRot.GetType().InvokeMember("GetSCriptingEngine", System.Reflection.BindingFlags.InvokeMethod,
null, SapGuilRot, null);
SAPconnection.sapGuiApp = engine as GuiApplication;
GuiConnection connection = sapGuiApp.Connections.ElementAt(0) as GuiConnection;
GuiSession session = connection.Children.ElementAt(0) as GuiSession;
MessageBox.Show(session.Info.User + " !!||!! " + session.Info.Transaction);
}
Use This method, you have to reference SapROTWr.DLL which is in the sapgui folder of your SAP installation.

This works for me (SAP 730 / Win7):
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using SAPFEWSELib;
using SapROTWr;
namespace FIT.SapHelper
{
public static class stcSapHelper
{
public static void testConnection()
{
SapROTWr.CSapROTWrapper sapROTWrapper = new SapROTWr.CSapROTWrapper();
object SapGuilRot = sapROTWrapper.GetROTEntry("SAPGUI");
object engine = SapGuilRot.GetType().InvokeMember("GetScriptingEngine", System.Reflection.BindingFlags.InvokeMethod, null, SapGuilRot, null);
GuiConnection connection = (engine as GuiApplication).OpenConnection("BOX DESCRIPTION");
GuiSession session = connection.Children.ElementAt(0) as GuiSession;
}
}
}

Assuming that SAPGUI is a COM object then you should be able to take a reference to it and create it as a new object without using reflection. i.e. Use early binding and not late binding even though the original VB6 code is using 'late binding'
Secondly, assuming late binding, shouldn't the Type.GetTypeFromProgID("SapGui.S‌criptingCtrl.1") fragment be Type.GetTypeFromProgID("SapGui") to match the original VB6? you might need to check on the object model for SAPGUI to make sure you're referencing the right object.

the only solution that i found to work with running sessions is to load that code in a dll and access it via c#

SAP released SAP .NET connector to provide standartized way to interact with SAP system from within of .NET application. Look at http://service.sap.com/connectors, you must be SAP partner to be able access to the page

How to release COM handle in .NET

I am using the following code under ASP.NET 4.0 framework to obtain the version of MSI file from a web app:
string strVersion = "";
try
{
Type InstallerType;
WindowsInstaller.Installer installer;
InstallerType = Type.GetTypeFromProgID("WindowsInstaller.Installer");
installer = (WindowsInstaller.Installer)Activator.CreateInstance(InstallerType);
WindowsInstaller.Database db = installer.OpenDatabase(strMSIFilePath, 0);
WindowsInstaller.View dv = db.OpenView("SELECT `Value` FROM `Property` WHERE `Property`='ProductVersion'");
WindowsInstaller.Record record = null;
dv.Execute(record);
record = dv.Fetch();
strVersion = record.get_StringData(1).ToString();
dv.Close();
//db.Commit();
System.Runtime.InteropServices.Marshal.FinalReleaseComObject(dv);
System.Runtime.InteropServices.Marshal.FinalReleaseComObject(db);
}
catch
{
//Failed
strVersion = "";
}
It works fine except that when the code finishes running it holds an internal MSI file handle so when I try to move or rename the MSI file I get the error that the file is still in use. This continues until I actually navigate away from the ASPX page that calls the method above.
My question is, I obviously didn't close some handle or object in the code above. But what could that be?
PS. I'm testing it in a development IDE from VS2010.
EDIT: Edited the code like it should be after Adriano's suggestion. Thanks!

The COM object has not been released (it should be auto-released when it goes out of scope but in .NET this doesn't work really well). Because it does not implement the IDisposable interface you can't call its Dispose() method and you can't use it inside an using statement. You have to explicitly call Marshal.FinalReleaseComObject. For example:
try
{
// Your stuffs
}
finally
{
dv.Close();
Marshal.FinalReleaseComObject(dv);
Marshal.FinalReleaseComObject(db);
}
Moreover note that you do not really need a call to the Commit() method because you didn't make any change but just a query.

FWIW, you should be using Windows Installer XML (WiX) Deployment Tools Foundation (DTF). It's an FOSS project from Microsoft that can be found on CodePlex. It has MSI interop libraries with classes that are very similar to the COM classes but implement IDisosable and use P/Invoke instead of COM behind the scenes. There is even support for Linq to MSI if you want. And the full source code is available.
DTF is the gold standard for MSI interop in a .NET world. Here are two examples:
using System;
using System.Linq;
using Microsoft.Deployment.WindowsInstaller;
using Microsoft.Deployment.WindowsInstaller.Linq;
namespace ConsoleApplication3
{
class Program
{
const string DATABASE_PATH = #"C:\FOO..MSI";
const string SQL_SELECT_PRODUCTVERSION = "SELECT `Value` FROM `Property` WHERE `Property`='ProductVersion'";
static void Main(string[] args)
{
using (Database database = new Database(DATABASE_PATH, DatabaseOpenMode.ReadOnly))
{
Console.WriteLine(database.ExecuteScalar(SQL_SELECT_PRODUCTVERSION).ToString());
}
using (QDatabase database = new QDatabase(DATABASE_PATH, DatabaseOpenMode.ReadOnly))
{
var results = from property in database.Properties where property.Property == "ProductVersion" select property.Value;
Console.WriteLine(results.AsEnumerable<string>().First());
}
}
}
}

try to Dispose the Objects.
dv.Dispose();
db.Dispose();

Razor Syntax / WebMatrix - C# Question

In Windows Forms I can create a class file called 'Authentication.cs' with the following code:
public class Authentication
{
public string Name;
internal bool Authenticate()
{
bool i = false;
if (Name == "Jason")
{
i = true;
}
return i;
}
}
In WebMatrix, I can insert a new Class file, called 'Authentication.cs', and insert the above code.
And in my default.cshtml file, I do this:
<body>
#{
Authentication auth = new Authentication();
if(auth.Authenticated("jasonp"))
{
<p>#auth.Authenticated("jasonp");</p>
}
}
</body>
But it won't work! It works for the WinForms desktop app, but not in WebMatrix. I don't know why it's not working. The error message is:
"The namespace Authenticate does not
exist. Are you sure you have
referenced assemblies etc?"
So, then at the top of my default.cshtml file I tried this:
#using Authentication.cs;
Which led to the exact same error!
There's no documentation that I can find anywhere that tells you how to "include" a class file into your WebMatrix pages.
Any help is appreciated,
Thank you!

You import a namespace, not a file. So; what namespace is Authentication in? For example:
#using My.Utils.Authentication.cs;
Also - you want to drop the ; in the razor call:
<p>#auth.Authenticated("jasonp")</p>
You can also provide the fully qualified name in the code:
#{
var auth = new My.Utils.Authentication();
if(auth.Authenticated("jasonp"))
{
<p>#auth.Authenticated("jasonp")</p>
}
}
(aside: are you intentionally calling the same method twice with the same values?)

Just drop the cs file in you App_Code directory
then do something like this
#{
Authentication auth = new Authentication();
if(auth.Authenticated("jasonp"))
{
<p>#auth.Authenticated("jasonp");</p>
}
}
No need to add a using.
Additionally if you wanted to use a .dll then you would need the using
#using NameSpace.Authenication
#{
Authenticated auth = new Authenicated();
}
#if(#auth.Authenticated("jasonp"))
{
<p>#auth.Authenticated("jasonp")</p>
}

Create a file named linkRef.cs
code:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
public class linkRef
{
public linkRef() {
//
// TODO: Add constructor logic here
//
}
}
Put it in a folder App_code then by dot net 2012 publish to bin then upload bin folder

Application.ProductName equivalent in WPF?

I have a class library that is nested two+ layers under a main GUI application, within that nested class library I want to be able to access the main applications name.
Under .Net 3.5 you could call Application.ProductName to retrieve the value from the Assembly.cs file, but I cannot identify an equivalent in WPF. If I use reflection and GetExecutingAssembly then it returns the class libraries details?
Thanks

You can use Assembly.GetEntryAssembly() to get the EXE assembly, and can then use Reflection to get the AssemblyProductAttribute from that.
This assumes that the product name has been set on the EXE assembly. The WinForms Application.ProductName property actually looked in the assembly containing the main form, so it works even if the GUI is built in a DLL. To replicate this in WPF you would use Application.Current.MainWindow.GetType().Assembly (and again use Reflection to get the attribute).

Here is another solution that I am using to get the Product Name
Public Shared Function ProductName() As String
If Windows.Application.ResourceAssembly Is Nothing Then
Return Nothing
End If
Return Windows.Application.ResourceAssembly.GetName().Name
End Sub

in wpf there are many way to do this ,
here you can find two of this.
using System;`
using System.Windows;
String applicationName = String.Empty;
//one way
applicationName = AppDomain.CurrentDomain.FriendlyName.Split('.')[0];
//other way
applicationName = Application.ResourceAssembly.GetName().Name;

If you need to get the descriptive product name as I did, then this solution may be useful:
// Get the Product Name from the Assembly information
string productName = String.Empty;
var list = Application.Current.MainWindow.GetType().Assembly.GetCustomAttributes(typeof(AssemblyProductAttribute), true);
if (list != null)
{
if (list.Length > 0)
{
productName = (list[0] as AssemblyProductAttribute).Product;
}
}
It returns whatever you've set for the 'AssemblyProduct' attribute in the AssemblyInfo.cs file, e.g. something like "Widget Engine Professional".

Based on the answers above, this works just great immediately:
var productName = Assembly.GetEntryAssembly()
.GetCustomAttributes(typeof(AssemblyProductAttribute))
.OfType<AssemblyProductAttribute>()
.FirstOrDefault().Product;

If you are looking for the values provided by the assembly information, e.g. the title...
... then you have to get the custom attributes like this:
using System.Linq;
using System.Reflection;
using System.Windows;
namespace WpfApp1
{
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
Title = (Assembly.GetEntryAssembly().GetCustomAttributes(typeof(AssemblyTitleAttribute)).SingleOrDefault() as AssemblyTitleAttribute)?.Title;
}
}
}

The answer you require is:
Path.GetFileName(Assembly.GetEntryAssembly().GetName().Name)