Solution that I am working on is made of number of projects, one of them is start-up project(Windows Forms, .exe project) and has app.config file tied to it. At least one of the project(all other projects are .DLLs), that deals with database, will also needs to read app.config settings (to read db connection string). I want to centralize all of the application settings in one app.config file.
My questions are:
From what I understood, application configuration files are created per projects, not per solution ?
To access the app.config from DLLs should I use ConfigurationManager.OpenExeConfiguration(string exePath), where string exePath is the location of .exe for start-up project ?
Config files are connected to application domains, not DLLs. You can access your appication's (let's say web application or console application) configuration directly with ConfigurationManager class (OpenExeConfiguration not required).
If you need different connection strings in different part's of the application, you can add multiple connectionstrings in your configuration
<connectionStrings>
<add name="Connection1" connectionString="Data Source=..." />
<add name="Connection2" connectionString="Data Source=..." />
</connectionStrings>
and access them by name:
var connectionstring1 = ConfigurationManager.ConnectionStrings["Connection1"].ConnectionString;
var connectionstring2 = ConfigurationManager.ConnectionStrings["Connection2"].ConnectionString;
Visual Studio creates an app.config for each project, but only to provide a place to store configuration items for that assembly (since it could be used by multiple executing assemblies). Those configuration items should be incorporated into the app.config of the executing assembly.
You can add code to pull from multiple config files, but it's cleaner just to put them all in one app.config for the executable.
You need to copy all the project specific configuration (like connections strings etc.) into the the main app.config.
Related
Just a quick question. I have a solution splitted in multiple projects. In one project, I have the database interactions and my EDMX. In this project, I have my app.config file with some connections strings.
This project, is imported as dependancy in a Web project. In this one, I have my Web.config where are defined (or "overriden") connections strings.
I'd like to know what are the mechanisms used to configure the database connection. From what I understood, the Web.config has all priority over App.config. But what I'm wondering is, is the App.config in dependancies projects used at compilation time ?
For instance :
Project A => app.config :
<connectionStrings>
<add name="A" connectionString="myConnectionStringA"/>
<add name="B" connectionString="myConnectionStringB"/>
</connectionStrings>
And the same in Web.config but with :
<connectionStrings>
<add name="A" connectionString="myConnectionStringC"/>
<add name="B" connectionString="myConnectionStringD"/>
</connectionStrings>
Which one will be used to define the connection to the EDMX ? In one hand, at compile time, logically it would be A & B used to define it, and C & D would be used at runtime.
But i'm not sure about it and for me, once the dll is "configured", I don't see how can C and D be used instead of A & B.
Could someone explain it to me please ?
Thanks !
The config file that is used at runtime is the one related to where you are launching your application. If you launch the projectA it will be the App.config file.
Actually it will be the file generated by the compilation on the proper directory "Debug" or "Release"
When you run your web project it will be the Web.config file there.
The dll isn't "configured" with the values from the config file, they are read when the application starts running and this will depend on the application that is running.
That is why if you change the values they will change when you relaunch the application without any need to recompile the project.
When designing your entities in Visual Studio, the connection string that is stored in the app.config file of the project is used.
Even though you add a reference to the project from the web project, the app.config of the referenced project is not used at all in the context of the web project. Of course, it can be used as a blueprint when adding the connection strings to the web.config.
The config file that is relevant to the web project is the web.config. So when running or publishing the web project, the settings that are used are the ones in the web.config.
They do not override the settings of the app.config in the sense of a fallback like "if the connection string is not configured in the web.config file, then I use the ones stored in app.config".
It is required that you add the connection strings that you want to use when running the web project to the web.config file, otherwise you'd encounter an error if you used the Entity classes.
For details on configuring ASP.NET web applications, see this link.
But i'm not sure about it and for me, once the dll is "configured", I
don't see how can C and D be used instead of A & B.
The config values are fetched when the progam is running, not when it is compiled.
Set & settings:
I use Entity Framework 5 and have a dll project with edmx file. In this project I have App.config with connection string for the EF model. I have also second project, ASP.MVC 4 web application which is a startup project. It references the database project. Important thing is - db is Oracle and EF uses Oracle custom providers.
Problem:
If I place my connection string in the ASP.MVC startup project is works fine. It's common advice to do this. But I don't want to. I don't see reason why I should. How can I force MVC/EF to find the connection string in App.config of the external library (which as a matter of fact is a data access layer)?
App.Config is used by WinForms, WPF and executable applications.
Web.Config is used in IIS (and is able to set IIS environment specific configurations)
It seems no App.Config will ever be merged to the Web.Config (source):
In using an App.config, file the configuration system merges the
App.config file with content of the Machine.config file when the
application starts and the configuration is applied. This mechanism
allows machine-wide settings to be defined in the Machine.config file.
The App.config file can be used to override the settings of the
Machine.config file; you can also lock in the settings in
Machine.config file so that they get used. In the Web.config case, the
configuration system merges the Web.config files in all directories
leading up to the application directory into the configuration that
gets applied. For more information about configuration and the setting
priorities, see topics in the System.Configuration namespace.
Perhaps you'll find a solution more appropriate to your needs by using Application Configuration Files.
Finally, after facing multiple issues, I've decided to move connection string of DAL into the Web.config of the web application. I was convinced by some arguments you can read here in the post of Chris Ammerman.
I have an MVC website that also references another Class project in my solution called DAL
The MVC website has a settings.settings file that I am using for my Default database connection string, and this automatically gets updated in my Web.Config file.
However my Class project also uses a settings.settings file for a database connection (to create a connection if one is not already supplied to it by the MVC project) and I believe this is put into the App.Config file, but when it comes to deploying and running this MVC website?
What do I do for the DAL project?
I can see it has a DAL\bin\release\DAL.dll.config file in that location, does this need to go into the root of the website directory, using the same file path? or should I be doing something else?
Thanks
You should be able to override this setting in your web.config by using the full name. If your project is called DAL you should create a connection string in your web.config which looks something like.
<add name="DAL.Properties.Settings.MyDatabaseConnectionString"
connectionString="Data Source=(local);Initial Catalog=myDatabase;Integrated Security=true"
providerName="System.Data.SqlClient" />
I have some values that I want to be able to set, and the application to load them from some kind of file.
The only concept I can think of, is a simple txt file, that might have the following lines:
DatabaseName = "DB1/test"
DatabasePassword = "password"
Development = "true"
but im thinking it should be in some kind of config file? Plus reading a txt file for these values isnt exactly tidy code. It would be nice if i could get the database name by just saying in my application:
configfile.DatabaseName
Thanks,
Paul
You really should be using the built in Application Settings
You can directly access simple settings using the ConfigurationManager
ConfigurationManager.AppSettings["MySetting"] = "SomeStuff";
var mySetting = ConfigurationManager.AppSettings["MySetting"];
There is also direct access to your Connection Strings using the ConfigurationManager
var conn = ConfigurationManager.ConnectionStrings["DevSqlServer"];
All this is stored in XML files, and by default your *.config files.
To Answer Doomsknight's question from the comments
Configuration settings can be done a number of ways, but by default, they are stored in two places.
Application Level Settings are stored in a configuration file.
For executable programs this file is located in the same directory as the .exe and is named after the assembly, or executable.
Example: MyAssembly.config, Another.Assembly.config
For web applications, the settings are stored in the web.config file (usually) located in the root directory of the web application. These are applied hierarchically and one can be located at each directory level of the Web Application.
Example: MySite\web.config, MySite\SubDirectory\web.config
User Scoped Settings are stored in the user profile
Example: C:\Documents and Settings\USERNAME\Local Settings\Application Data\ApplicationName
Connection Strings are stored in the <connectionStrings></connectionStrings> section in your config file.
<connectionStrings>
<clear />
<add name="Name"
providerName="System.Data.ProviderName"
connectionString="Valid Connection String;" />
</connectionStrings>
These settings can easily be modified directly in the config file, but without writing some code to automatically refresh sections of the config file (which is possible), an application restart is typically needed.
I hope this helps out.
.NET has a configuration platform built into it. Just add an app.config file to your project and use the ConfigurationManager library to access the values.
I created the setup project for the application and I can see that the later modifications of the configuration file (Application.exe.config) don't affect the application execution.
I am developing an application with the database file included and I want to enable users to move the database file and modify connection strings.
Does anyone know what's the best practice for the deployment of the application with the database file?
It should work, provided that you use the exact same connection string setting in your DB access DLL's Settings.settings file and in your application's config file.
An example that works well for me:
<connectionStrings>
<add name="YourApp.Properties.Settings.DatabaseConnectionString"
connectionString="Data Source=localhost;Initial Catalog=xxx;Integrated Security=True;"
providerName="System.Data.SqlClient" />
</connectionStrings>
When entered appropriately in both locations (ie. the dll's Settings.settings and the exe's App.config files), this does allow me to change the database connection in YourApp.exe.config before the app runs.
(I assume you already know that you need to change the application's config file, as DLL's do not support the app.config mechanism directly.)
Have you checked out using a UDL file?
If you save your connection string in the udl file, the user can change the connection via an interface by simply double clicking that file.
You can set your connection string in the app to point to the udl file.
You can also launch the udl interface programmatically if you want.
The only downside to these is if the user saves their password to the file, it is saved as plain text. But this isn't an issue if you are using windows authentication.
did you make sure to remove the settings default values? These are compiled and fetched from the dll and not from the config file.