We have a WPF application which is extensible with external components developed in-house. Some external components requires new section (in this case, EntityFrameworkSection) to be added into the app.config of the WPF application during the installation of the component. However, EntityFrameworkSection doesn't seems to accessible as it is an internal class.
Our question is, is it possible for us to programmatically add EntityFrameworkSection into app.config?
Since I'm happen to use EF6, I ended up using code base configuration which is available since EF6. In my case, I'm trying to add configuration related to MySQL. Basically what we need to do is to derive from DbConfiguration and set it as the configuration for EF. Following is what I comes up with:
Deriving from DbConfiguration...
public class CustomDbConfiguration : DbConfiguration
{
public CustomDbConfiguration()
{
SetProviderServices(MySqlProviderInvariantName.ProviderName, new MySqlProviderServices());
SetProviderFactory(MySqlProviderInvariantName.ProviderName, new MySqlClientFactory());
}
}
and use it like this:
class Program
{
// 'DbConfiguration' should be treated as readonly. ONE AND ONLY ONE instance of
// 'DbConfiguration' is allowed in each AppDomain.
private static readonly CustomDbConfiguration DBConfig = new CustomDbConfiguration();
static void Main(string[] args)
{
// Explicitly set the configuration before using any features from EntityFramework.
DbConfiguration.SetConfiguration(DBConfig);
using (var dbContext = new MySQLDb())
{
var dbSet = dbContext.Set<Actor>();
// Read data from database.
var actors = dbSet.ToList();
}
using (var dbContext = new SQLDb())
{
var dbSet = dbContext.Set<User>();
// Read data from database.
var users = dbSet.ToList();
}
}
}
My app.config only contains info for connection string, as follow:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.6.1" />
</startup>
<connectionStrings>
<add name="MySQLDb" connectionString="server=localhost;port=3306;database=sakila;uid=some_id;password=some_password" providerName="MySql.Data.MySqlClient"/>
<add name="SQLDb" connectionString="data source=.\SQLEXPRESS;initial catalog=some_db;integrated security=True;MultipleActiveResultSets=True;App=EntityFramework" providerName="System.Data.SqlClient" />
</connectionStrings>
</configuration>
Bit new on EF. I'm, creating application where user selects database from computer. and now i want to change connection string to match location of the database for example : this is current connection string that points to database location somewhere on disk (C:\Users\student\Documents\TestData.md) :
add name="test" connectionString="metadata=res://*/Model2.csdl|res://*/Model2.ssdl|res://*/Model2.msl;provider=System.Data.SqlClient;provider connection string='data source=(LocalDB)\v11.0;attachdbfilename="C:\Users\student\Documents\TestData.mdf";integrated security=True;connect timeout=30;MultipleActiveResultSets=True;App=EntityFramework'" providerName="System.Data.EntityClient" />
now when user selects new database from disk the connection sting needs to change to location where new database is located (C:\Users\student\Desktop\NewSelectedDatabase.mdf) :
add name="test" connectionString="metadata=res://*/Model2.csdl|res://*/Model2.ssdl|res://*/Model2.msl;provider=System.Data.SqlClient;provider connection string='data source=(LocalDB)\v11.0;attachdbfilename="C:\Users\student\Desktop\NewSelectedDatabase.mdf";integrated security=True;connect timeout=30;MultipleActiveResultSets=True;App=EntityFramework'" providerName="System.Data.EntityClient" />
now i've created filedialog so user can select database and to get its adress . i've also changed my edmax to to recive custom connection string :
public partial class Tester : DbContext
{
public Tester()
: base("name=Test")
{
}
public Tester(string customcs)
: base(customcs)
{
}
now my problem is what do i pass to constructor as custom connection string ? i hope you understood me because i'm realy bad at english and explainig things
When you have the EF designer up, on the properties window is a connectionstring setting. Once you have everything set as you like, clear that setting to none. It rewrites the generated code to accept a connection string passed in on instantiating.
var mything= new dbcontext (connstring)
Another option would be to just create a new class (.cs) file giving it the same namespace that your Tester EF context belongs to, and paste this in there:
public partial class Tester : DbContext {
public Tester(string _connectionString) : base(ConnectionString(_connectionString)) {
this.Configuration.ProxyCreationEnabled = false;
this.Configuration.AutoDetectChangesEnabled = false;
}
private static string ConnectionString(string _connectionString) {
EntityConnectionStringBuilder entityBuilder = new EntityConnectionStringBuilder();
entityBuilder.ProviderConnectionString = _connectionString;
entityBuilder.Metadata = "res://*/Models.Tester.csdl|res://*/Models.Tester.ssdl|res://*/Models.Tester.msl";
entityBuilder.Provider = "System.Data.SqlClient";
return entityBuilder.ToString();
}
}
Notice it's a partial class (just like the auto-generated ones for Tester are) -- and so you're adding to the auto-generated class made by EF (again, make sure they're in the same namespaces, so it really is an addition to the partial class, not just you off making your own little one).
This way, you're adding a new construction instantiation (that's passing a connection string) that gets modified into the right entity-connection-string builder (via the private static ConnectionString method).
var myThing = new Tester(ConfigurationManager.ConnectionStrings["db_DBName"].ToString());
I have one line in the web.config for the connection:
<add name="db_DBName" connectionString="Data Source=DBSERVER;initial Catalog=DBNAME;" providerName="System.Data.SqlClient" />
the build target defines its transformantion, and I just pass the same string into the code all the time.
hi i am generated an CRUD operations in entity frame work in mvc4. Now i Unit test that classes .. i am using the following code in controller for creation
[HttpPost]
public ActionResult Create(Member member)
{
if (ModelState.IsValid)
{
db.Members.Add(member);
db.SaveChanges();
return RedirectToAction("Index");
}
return View(member);
}
and i am using the test code for testing this is,
[TestMethod]
public void Create()
{
MemberController me = new MemberController();
var mem = new Member();
mem.MemID = 123;
mem.MemName = "sruthy";
var result = (RedirectToRouteResult)me.Create(mem);
Assert.AreEqual("Index", result.RouteValues["action"]);
}
i am just try to test the create class. but it shows the following error
Test failed: Create
Message: Test method SmpleTest.MemberTest.Create threw exception:
System.data>ProviderIncomactibleException:An error occured while
getting provider information from the database. This can be cased by
Entity Framework using an incorrect connection string. Check the inner
exception for details and ensure that the connection string is
correct.--->System.data.ProviderIncompatibleException:The provide did
not return a ProviderManifestToken string.--->
System.Data.SqlClient.SqlException:A network- related or intace
specific error occured while establishing a connection to SQL Server.
The server was not found or was not accesable. Varify that the
instance name is correct and the SQL Server is configured to allow
remote connections.(proider:SQL Network Interfaces, error:26-Error
Locating Server/Instance Specified)
This is my connection string
<connectionStrings>
<add name="SampleDataContext" connectionString="Data Source=(LocalDb)\v11.0;Initial Catalog=Sample;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|\Sample.mdf" providerName="System.Data.SqlClient" />
</connectionStrings>
Normally Create operation is worked with this connection string. Can anybody please help me to identify the problem. Thank you
Please add the connection string in test case project and your return action is Create not the Index.
We're having lots of problems trying to get the MvcMiniProfiler to work with our EF implementation of the Repository Pattern.
Error:
The entity type CustomEntityPewPewFooFoo is not part of the model for
the current context.
Ok. this is the code we've done.
Custom UnitOfWork Context class
public class UnitOfWork : DbContext
{
public UnitOfWork(string connectionString)
: base(GetProfiledConnection(connectionString))
{ }
private static DbConnection GetProfiledConnection(string connectionString)
{
var parsedConnectionString = new
EntityConnectionStringBuilder(connectionString);
var connection = new
SqlConnection(parsedConnectionString.ProviderConnectionString);
return ProfiledDbConnection.Get(connection);
}
public void Commit() { ... }
}
Add the factory settings stuff...
// NOTE: If this is not added, I get an error:
// Unable to find the requested .Net Framework Data Provider.
// It may not be installed.
// In web.config ...
<system.data>
<DbProviderFactories>
<remove invariant="MvcMiniProfiler.Data.ProfiledDbProvider" />
<add name="MvcMiniProfiler.Data.ProfiledDbProvider" invariant="MvcMiniProfiler.Data.ProfiledDbProvider" description="MvcMiniProfiler.Data.ProfiledDbProvider" type="MvcMiniProfiler.Data.ProfiledDbProviderFactory, MvcMiniProfiler, Version=1.7.0.0, Culture=neutral, PublicKeyToken=b44f9351044011a3" />
</DbProviderFactories>
</system.data>
And finally, add this extra stuff....
// global.asax, in Application_Start().. because I'm caching
// some database data on startup.
var factory = new SqlConnectionFactory(ConfigurationManager.ConnectionStrings[0].ConnectionString);
var profiled = new MvcMiniProfiler.Data.ProfiledDbConnectionFactory(factory);
Database.DefaultConnectionFactory = profiled;
LoadApplicationDataToBeCachedForAllRequests(); // Go and hit the Db! Go Forth!!!
My connection string...
<connectionStrings>
<clear />
<add name="XWing_SqlServer_EF" connectionString="metadata=res://*/SqlServer.XWingModel.csdl|
res://*/SqlServer.XWingModel.ssdl|
res://*/SqlServer.XWingModel.msl;provider=System.Data.SqlClient;
provider connection string='Data Source=Tarantino;Initial Catalog=XWing;Integrated Security=SSPI;MultipleActiveResultSets=True;'"
providerName="System.Data.EntityClient" />
</connectionStrings>
And finally (again), then edmx info ..
- Entity Container Name: XWingEntities
- Namespace: XWing.Repositories.SqlServer
- Filename: XWingModel.edmx
It might be that you have the same kind of problem I had here. Basically, if the UnitOfWork class is not in the same assembly as the edmx, it will not work.
Is it is possible to do something like the following in the app.config or web.config files?
<appSettings>
<add key="MyBaseDir" value="C:\MyBase" />
<add key="Dir1" value="[MyBaseDir]\Dir1"/>
<add key="Dir2" value="[MyBaseDir]\Dir2"/>
</appSettings>
I then want to access Dir2 in my code by simply saying:
ConfigurationManager.AppSettings["Dir2"]
This will help me when I install my application in different servers and locations wherein I will only have to change ONE entry in my entire app.config.
(I know I can manage all the concatenation in code, but I prefer it this way).
A slightly more complicated, but far more flexible, alternative is to create a class that represents a configuration section. In your app.config / web.config file, you can have this:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<!-- This section must be the first section within the <configuration> node -->
<configSections>
<section name="DirectoryInfo" type="MyProjectNamespace.DirectoryInfoConfigSection, MyProjectAssemblyName" />
</configSections>
<DirectoryInfo>
<Directory MyBaseDir="C:\MyBase" Dir1="Dir1" Dir2="Dir2" />
</DirectoryInfo>
</configuration>
Then, in your .NET code (I'll use C# in my example), you can create two classes like this:
using System;
using System.Configuration;
namespace MyProjectNamespace {
public class DirectoryInfoConfigSection : ConfigurationSection {
[ConfigurationProperty("Directory")]
public DirectoryConfigElement Directory {
get {
return (DirectoryConfigElement)base["Directory"];
}
}
public class DirectoryConfigElement : ConfigurationElement {
[ConfigurationProperty("MyBaseDir")]
public String BaseDirectory {
get {
return (String)base["MyBaseDir"];
}
}
[ConfigurationProperty("Dir1")]
public String Directory1 {
get {
return (String)base["Dir1"];
}
}
[ConfigurationProperty("Dir2")]
public String Directory2 {
get {
return (String)base["Dir2"];
}
}
// You can make custom properties to combine your directory names.
public String Directory1Resolved {
get {
return System.IO.Path.Combine(BaseDirectory, Directory1);
}
}
}
}
Finally, in your program code, you can access your app.config variables, using your new classes, in this manner:
DirectoryInfoConfigSection config =
(DirectoryInfoConfigSection)ConfigurationManager.GetSection("DirectoryInfo");
String dir1Path = config.Directory.Directory1Resolved; // This value will equal "C:\MyBase\Dir1"
You can accomplish using my library Expansive. Also available on nuget here.
It was designed with this as a primary use-case.
Moderate Example (using AppSettings as default source for token expansion)
In app.config:
<configuration>
<appSettings>
<add key="Domain" value="mycompany.com"/>
<add key="ServerName" value="db01.{Domain}"/>
</appSettings>
<connectionStrings>
<add name="Default" connectionString="server={ServerName};uid=uid;pwd=pwd;Initial Catalog=master;" provider="System.Data.SqlClient" />
</connectionStrings>
</configuration>
Use the .Expand() extension method on the string to be expanded:
var connectionString = ConfigurationManager.ConnectionStrings["Default"].ConnectionString;
connectionString.Expand() // returns "server=db01.mycompany.com;uid=uid;pwd=pwd;Initial Catalog=master;"
or
Use the Dynamic ConfigurationManager wrapper "Config" as follows (Explicit call to Expand() not necessary):
var serverName = Config.AppSettings.ServerName;
// returns "db01.mycompany.com"
var connectionString = Config.ConnectionStrings.Default;
// returns "server=db01.mycompany.com;uid=uid;pwd=pwd;Initial Catalog=master;"
Advanced Example 1 (using AppSettings as default source for token expansion)
In app.config:
<configuration>
<appSettings>
<add key="Environment" value="dev"/>
<add key="Domain" value="mycompany.com"/>
<add key="UserId" value="uid"/>
<add key="Password" value="pwd"/>
<add key="ServerName" value="db01-{Environment}.{Domain}"/>
<add key="ReportPath" value="\\{ServerName}\SomeFileShare"/>
</appSettings>
<connectionStrings>
<add name="Default" connectionString="server={ServerName};uid={UserId};pwd={Password};Initial Catalog=master;" provider="System.Data.SqlClient" />
</connectionStrings>
</configuration>
Use the .Expand() extension method on the string to be expanded:
var connectionString = ConfigurationManager.ConnectionStrings["Default"].ConnectionString;
connectionString.Expand() // returns "server=db01-dev.mycompany.com;uid=uid;pwd=pwd;Initial Catalog=master;"
Good question.
I don't think there is. I believe it would have been quite well known if there was an easy way, and I see that Microsoft is creating a mechanism in Visual Studio 2010 for deploying different configuration files for deployment and test.
With that said, however; I have found that you in the ConnectionStrings section have a kind of placeholder called "|DataDirectory|". Maybe you could have a look at what's at work there...
Here's a piece from machine.config showing it:
<connectionStrings>
<add
name="LocalSqlServer"
connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|aspnetdb.mdf;User Instance=true"
providerName="System.Data.SqlClient"
/>
</connectionStrings>
Usally, I end up writing a static class with properties to access each of the settings of my web.config.
public static class ConfigManager
{
public static string MyBaseDir
{
return ConfigurationManager.AppSettings["MyBaseDir"].toString();
}
public static string Dir1
{
return MyBaseDir + ConfigurationManager.AppSettings["Dir1"].toString();
}
}
Usually, I also do type conversions when required in this class. It allows to have a typed access to your config, and if settings change, you can edit them in only one place.
Usually, replacing settings with this class is relatively easy and provides a much greater maintainability.
I thought I just saw this question.
In short, no, there's no variable interpolation within an application configuration.
You have two options
You could roll your own to substitute variables at runtime
At build time, massage the application configuration to the particular specifics of the target deployment environment. Some details on this at dealing with the configuration-nightmare
You have a couple of options. You could do this with a build / deploy step which would process your configuration file replacing your variables with the correct value.
Another option would be to define your own Configuration section which supported this. For example imagine this xml:
<variableAppSettings>
<variables>
<add key="#BaseDir" value="c:\Programs\Widget"/>
</variables>
<appSettings>
<add key="PathToDir" value="#BaseDir\Dir1"/>
</appSettings>
</variableAppSettings>
Now you would implement this using custom configuration objects which would handle replacing the variables for you at runtime.
You can use environment variables in your app.config for that scenario you describe
<configuration>
<appSettings>
<add key="Dir1" value="%MyBaseDir%\Dir1"/>
</appSettings>
</configuration>
Then you can easily get the path with:
var pathFromConfig = ConfigurationManager.AppSettings["Dir1"];
var expandedPath = Environment.ExpandEnvironmentVariables(pathFromConfig);
Inside <appSettings> you can create application keys,
<add key="KeyName" value="Keyvalue"/>
Later on you can access these values using:
ConfigurationManager.AppSettings["Keyname"]
I would suggest you DslConfig. With DslConfig you can use hierarchical config files from Global Config, Config per server host to config per application on each server host (see the AppSpike).
If this is to complicated for you you can just use the global config Variables.var
Just configure in Varibales.var
baseDir = "C:\MyBase"
Var["MyBaseDir"] = baseDir
Var["Dir1"] = baseDir + "\Dir1"
Var["Dir2"] = baseDir + "\Dir2"
And get the config values with
Configuration config = new DslConfig.BooDslConfiguration()
config.GetVariable<string>("MyBaseDir")
config.GetVariable<string>("Dir1")
config.GetVariable<string>("Dir2")
I don't think you can declare and use variables to define appSettings keys within a configuration file. I've always managed concatenations in code like you.
I'm struggling a bit with what you want, but you can add an override file to the app settings then have that override file set on a per environment basis.
<appSettings file="..\OverrideSettings.config">
For rolling out products where we need to configure a lot of items with similar values, we use small console apps that read the XML and update based on the parameters passed in. These are then called by the installer after it has asked the user for the required information.
I would recommend following Matt Hamsmith's solution. If it's an issue to implement, then why not create an extension method that implements this in the background on the AppSettings class?
Something like:
public static string GetValue(this NameValueCollection settings, string key)
{
}
Inside the method you search through the DictionaryInfoConfigSection using Linq and return the value with the matching key. You'll need to update the config file though, to something along these lines:
<appSettings>
<DirectoryMappings>
<DirectoryMap key="MyBaseDir" value="C:\MyBase" />
<DirectoryMap key="Dir1" value="[MyBaseDir]\Dir1"/>
<DirectoryMap key="Dir2" value="[MyBaseDir]\Dir2"/>
</DirectoryMappings>
</appSettings>
I came up with this solution:
In the application Settings.settings I defined a variable ConfigurationBase (with type=string Scope=Application)
I introduced a variable in the target attributes in the Settings.settings, all those attributes had to be set to Scope=User
In the app.xaml.cs I read out the value if the ConfigurationBase
In the app.xaml.cs I replaced all variables with the ConfigurationBase value. In order to replace the values at run-time the attributes had to be set to Scopr=User
I'm not really happy with this solution because I have to change all attributes manually, if I add a new one I have to regard it in the app.xaml.cs.
Here a code snippet from the App.xaml.cs:
string configBase = Settings.Default.ConfigurationBase;
Settings.Default.CommonOutput_Directory = Settings.Default.CommonOutput_Directory.Replace("${ConfigurationBase}", configBase);
UPDATE
Just found an improvement (again a code snippet from the app.xaml.cs):
string configBase = Settings.Default.ConfigurationBase;
foreach (SettingsProperty settingsProperty in Settings.Default.Properties)
{
if (!settingsProperty.IsReadOnly && settings.Default[settingsProperty.Name] is string)
{
Settings.Default[settingsProperty.Name] = ((string)Settings.Default[settingsProperty.Name]).Replace("${ConfigurationBase}", configBase);
}
}
Now the replacements work for all attributes in my settings that have Type=string and Scope=User. I think I like it this way.
UPDATE2
Apparently setting Scope=Application is not required when running over the properties.
Three Possible Solutions
I know I'm coming late to the party, I've been looking if there were any new solutions to the variable configuration settings problem. There are a few answers that touch the solutions I have used in the past but most seem a bit convoluted. I thought I'd look at my old solutions and put the implementations together so that it might help people that are struggling with the same problem.
For this example I have used the following app setting in a console application:
<appSettings>
<add key="EnvironmentVariableExample" value="%BaseDir%\bin"/>
<add key="StaticClassExample" value="bin"/>
<add key="InterpollationExample" value="{0}bin"/>
</appSettings>
1. Use environment variables
I believe autocro autocro's answer touched on it. I'm just doing an implementation that should suffice when building or debugging without having to close visual studio. I have used this solution back in the day...
Create a pre-build event that will use the MSBuild variables
Warning: Use a variable that will not be replaced easily so use your project name or something similar as a variable name.
SETX BaseDir "$(ProjectDir)"
Reset variables; using something like the following:
Refresh Environment Variables on Stack Overflow
Use the setting in your code:
'
private void Test_Environment_Variables()
{
string BaseDir = ConfigurationManager.AppSettings["EnvironmentVariableExample"];
string ExpandedPath = Environment.ExpandEnvironmentVariables(BaseDir).Replace("\"", ""); //The function addes a " at the end of the variable
Console.WriteLine($"From within the C# Console Application {ExpandedPath}");
}
'
2. Use string interpolation:
Use the string.Format() function
`
private void Test_Interpollation()
{
string ConfigPath = ConfigurationManager.AppSettings["InterpollationExample"];
string SolutionPath = Path.GetFullPath(Path.Combine(System.AppDomain.CurrentDomain.BaseDirectory, #"..\..\"));
string ExpandedPath = string.Format(ConfigPath, SolutionPath.ToString());
Console.WriteLine($"Using old interpollation {ExpandedPath}");
}
`
3. Using a static class, This is the solution I mostly use.
The implementation
`
private void Test_Static_Class()
{
Console.WriteLine($"Using a static config class {Configuration.BinPath}");
}
`
The static class
`
static class Configuration
{
public static string BinPath
{
get
{
string ConfigPath = ConfigurationManager.AppSettings["StaticClassExample"];
string SolutionPath = Path.GetFullPath(Path.Combine(System.AppDomain.CurrentDomain.BaseDirectory, #"..\..\"));
return SolutionPath + ConfigPath;
}
}
}
`
Project Code:
App.config:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.6.1" />
</startup>
<appSettings>
<add key="EnvironmentVariableExample" value="%BaseDir%\bin"/>
<add key="StaticClassExample" value="bin"/>
<add key="InterpollationExample" value="{0}bin"/>
</appSettings>
</configuration>
Program.cs
using System;
using System.Configuration;
using System.IO;
namespace ConfigInterpollation
{
class Program
{
static void Main(string[] args)
{
new Console_Tests().Run_Tests();
Console.WriteLine("Press enter to exit");
Console.ReadLine();
}
}
internal class Console_Tests
{
public void Run_Tests()
{
Test_Environment_Variables();
Test_Interpollation();
Test_Static_Class();
}
private void Test_Environment_Variables()
{
string ConfigPath = ConfigurationManager.AppSettings["EnvironmentVariableExample"];
string ExpandedPath = Environment.ExpandEnvironmentVariables(ConfigPath).Replace("\"", "");
Console.WriteLine($"Using environment variables {ExpandedPath}");
}
private void Test_Interpollation()
{
string ConfigPath = ConfigurationManager.AppSettings["InterpollationExample"];
string SolutionPath = Path.GetFullPath(Path.Combine(System.AppDomain.CurrentDomain.BaseDirectory, #"..\..\"));
string ExpandedPath = string.Format(ConfigPath, SolutionPath.ToString());
Console.WriteLine($"Using interpollation {ExpandedPath}");
}
private void Test_Static_Class()
{
Console.WriteLine($"Using a static config class {Configuration.BinPath}");
}
}
static class Configuration
{
public static string BinPath
{
get
{
string ConfigPath = ConfigurationManager.AppSettings["StaticClassExample"];
string SolutionPath = Path.GetFullPath(Path.Combine(System.AppDomain.CurrentDomain.BaseDirectory, #"..\..\"));
return SolutionPath + ConfigPath;
}
}
}
}
Pre-build event:
Project Settings -> Build Events