I'm working on a C# class library that needs to be able to read settings from the web.config or app.config file (depending on whether the DLL is referenced from an ASP.NET web application or a Windows Forms application).
I've found that
ConfigurationSettings.AppSettings.Get("MySetting")
works, but that code has been marked as deprecated by Microsoft.
I've read that I should be using:
ConfigurationManager.AppSettings["MySetting"]
However, the System.Configuration.ConfigurationManager class doesn't seem to be available from a C# Class Library project.
What is the best way to do this?
For a sample app.config file like below:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<appSettings>
<add key="countoffiles" value="7" />
<add key="logfilelocation" value="abc.txt" />
</appSettings>
</configuration>
You read the above application settings using the code shown below:
using System.Configuration;
You may also need to also add a reference to System.Configuration in your project if there isn't one already. You can then access the values like so:
string configvalue1 = ConfigurationManager.AppSettings["countoffiles"];
string configvalue2 = ConfigurationManager.AppSettings["logfilelocation"];
You'll need to add a reference to System.Configuration in your project's references folder.
You should definitely be using the ConfigurationManager over the obsolete ConfigurationSettings.
Update for .NET Framework 4.5 and 4.6; the following will no longer work:
string keyvalue = System.Configuration.ConfigurationManager.AppSettings["keyname"];
Now access the Setting class via Properties:
string keyvalue = Properties.Settings.Default.keyname;
See Managing Application Settings for more information.
Right click on your class library, and choose the "Add References" option from the Menu.
And from the .NET tab, select System.Configuration. This would include the System.Configuration DLL file into your project.
I'm using this, and it works well for me:
textBox1.Text = ConfigurationManager.AppSettings["Name"];
Read From Config:
You'll need to add a reference to the configuration:
Open "Properties" on your project
Go to "Settings" Tab
Add "Name" and "Value"
Get Value with using following code:
string value = Properties.Settings.Default.keyname;
Save to the configuration:
Properties.Settings.Default.keyName = value;
Properties.Settings.Default.Save();
You must add a reference to the System.Configuration assembly to the project.
You might be adding the App.config file to a DLL file. App.Config works only for executable projects, since all the DLL files take the configuration from the configuration file for the EXE file being executed.
Let's say you have two projects in your solution:
SomeDll
SomeExe
Your problem might be related to the fact that you're including the app.config file to SomeDLL and not SomeExe. SomeDll is able to read the configuration from the SomeExe project.
Try this:
string keyvalue = System.Configuration.ConfigurationManager.AppSettings["keyname"];
In the web.config file this should be the next structure:
<configuration>
<appSettings>
<add key="keyname" value="keyvalue" />
</appSettings>
</configuration>
Step 1: Right-click on references tab to add reference.
Step 2: Click on Assemblies tab
Step 3: Search for 'System.Configuration'
Step 4: Click OK.
Then it will work.
string value = System.Configuration.ConfigurationManager.AppSettings["keyname"];
I had the same problem. Just read them this way:
System.Configuration.ConfigurationSettings.AppSettings["MySetting"]
web.config is used with web applications. web.config by default has several configurations required for the web application. You can have a web.config for each folder under your web application.
app.config is used for Windows applications. When you build the application in Visual Studio, it will be automatically renamed to <appname>.exe.config and this file has to be delivered along with your application.
You can use the same method to call the app settings values from both configuration files:
System.Configuration.ConfigurationSettings.AppSettings["Key"]
As I found the best approach to access application settings variables in a systematic way by making a wrapper class over System.Configuration as below
public class BaseConfiguration
{
protected static object GetAppSetting(Type expectedType, string key)
{
string value = ConfigurationManager.AppSettings.Get(key);
try
{
if (expectedType == typeof(int))
return int.Parse(value);
if (expectedType == typeof(string))
return value;
throw new Exception("Type not supported.");
}
catch (Exception ex)
{
throw new Exception(string.Format("Config key:{0} was expected to be of type {1} but was not.",
key, expectedType), ex);
}
}
}
Now we can access needed settings variables by hard coded names using another class as below:
public class ConfigurationSettings:BaseConfiguration
{
#region App setting
public static string ApplicationName
{
get { return (string)GetAppSetting(typeof(string), "ApplicationName"); }
}
public static string MailBccAddress
{
get { return (string)GetAppSetting(typeof(string), "MailBccAddress"); }
}
public static string DefaultConnection
{
get { return (string)GetAppSetting(typeof(string), "DefaultConnection"); }
}
#endregion App setting
#region global setting
#endregion global setting
}
Also, you can use Formo:
Configuration:
<appSettings>
<add key="RetryAttempts" value="5" />
<add key="ApplicationBuildDate" value="11/4/1999 6:23 AM" />
</appSettings>
Code:
dynamic config = new Configuration();
var retryAttempts1 = config.RetryAttempts; // Returns 5 as a string
var retryAttempts2 = config.RetryAttempts(10); // Returns 5 if found in config, else 10
var retryAttempts3 = config.RetryAttempts(userInput, 10); // Returns 5 if it exists in config, else userInput if not null, else 10
var appBuildDate = config.ApplicationBuildDate<DateTime>();
If your needing/wanting to use the ConfigurationManager class...
You may need to load System.Configuration.ConfigurationManager by Microsoft via NuGet Package Manager
Tools->NuGet Package Manager->Manage NuGet Packages for Solution...
Microsoft Docs
One thing worth noting from the docs...
If your application needs read-only access to its own configuration,
we recommend that you use the GetSection(String) method. This method
provides access to the cached configuration values for the current
application, which has better performance than the Configuration
class.
I strongly recommend you to create a wrapper for this call. Something like a ConfigurationReaderService and use dependency injection to get this class. This way you will be able to isolate this configuration files for test purposes.
So use the ConfigurationManager.AppSettings["something"]; suggested and return this value. With this method you can create some kind of default return if there isn't any key available in the .config file.
Just for completeness, there's another option available for web projects only:
System.Web.Configuration.WebConfigurationManager.AppSettings["MySetting"]
The benefit of this is that it doesn't require an extra reference to be added, so it may be preferable for some people.
I always create an IConfig interface with typesafe properties declared for all configuration values. A Config implementation class then wraps the calls to System.Configuration. All your System.Configuration calls are now in one place, and it is so much easier and cleaner to maintain and track which fields are being used and declare their default values. I write a set of private helper methods to read and parse common data types.
Using an IoC framework you can access the IConfig fields anywhere your in application by simply passing the interface to a class constructor. You're also then able to create mock implementations of the IConfig interface in your unit tests so you can now test various configuration values and value combinations without needing to touch your App.config or Web.config file.
Please check the .NET version you are working on. It should be higher than 4. And you have to add the System.Configuration system library to your application.
You can use the below line. In my case it was working:
System.Configuration.ConfigurationSettings.AppSettings["yourKeyName"]
You must take care that the above line of code is also the old version and it's deprecated in new libraries.
The ConfigurationManager is not what you need to access your own settings.
To do this you should use
{YourAppName}.Properties.Settings.{settingName}
I was able to get the below approach working for .NET Core projects:
Steps:
Create an appsettings.json (format given below) in your project.
Next create a configuration class. The format is provided below.
I have created a Login() method to show the usage of the Configuration Class.
Create appsettings.json in your project with content:
{
"Environments": {
"QA": {
"Url": "somevalue",
"Username": "someuser",
"Password": "somepwd"
},
"BrowserConfig": {
"Browser": "Chrome",
"Headless": "true"
},
"EnvironmentSelected": {
"Environment": "QA"
}
}
public static class Configuration
{
private static IConfiguration _configuration;
static Configuration()
{
var builder = new ConfigurationBuilder()
.AddJsonFile($"appsettings.json");
_configuration = builder.Build();
}
public static Browser GetBrowser()
{
if (_configuration.GetSection("BrowserConfig:Browser").Value == "Firefox")
{
return Browser.Firefox;
}
if (_configuration.GetSection("BrowserConfig:Browser").Value == "Edge")
{
return Browser.Edge;
}
if (_configuration.GetSection("BrowserConfig:Browser").Value == "IE")
{
return Browser.InternetExplorer;
}
return Browser.Chrome;
}
public static bool IsHeadless()
{
return _configuration.GetSection("BrowserConfig:Headless").Value == "true";
}
public static string GetEnvironment()
{
return _configuration.GetSection("EnvironmentSelected")["Environment"];
}
public static IConfigurationSection EnvironmentInfo()
{
var env = GetEnvironment();
return _configuration.GetSection($#"Environments:{env}");
}
}
public void Login()
{
var environment = Configuration.EnvironmentInfo();
Email.SendKeys(environment["username"]);
Password.SendKeys(environment["password"]);
WaitForElementToBeClickableAndClick(_driver, SignIn);
}
Another possible solution:
var MyReader = new System.Configuration.AppSettingsReader();
string keyvalue = MyReader.GetValue("keyalue",typeof(string)).ToString();
I have been trying to find a fix for this same issue for a couple of days now. I was able to resolve this by adding a key within the appsettings tag in the web.config file. This should override the .dll file when using the helper.
<configuration>
<appSettings>
<add key="loginUrl" value="~/RedirectValue.cshtml" />
<add key="autoFormsAuthentication" value="false"/>
</appSettings>
</configuration>
extra : if you are working on a Class Library project you have to embed the settings.json file.
A class library shouldn't really be directly referencing anything in
app.config - the class doesn't have an app.config, because it's not an
application, it's a class.
Go to the JSON file's properties.
Change Build Action -> Embedded resource.
Use the following code to read it.
var assembly = Assembly.GetExecutingAssembly();
var resourceStream = assembly.GetManifestResourceStream("Assembly.file.json");
string myString = reader.ReadToEnd();
now we have a JSON string we can Deserialize it using JsonConvert
if you didn't embed the file inside the assembly you can't use only the DLL file without the file
I'm using Visual Studio for Mac version 17.0.6.
As you can see on this screenshot it is not possible to add a reference to System.Configuration.
Solution:
install NuGet Package - System.Configuration.ConfigurationManager.
Create app.config file and set "Build action" to "EmbeddedResource"
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<appSettings>
<add key="name" value="Joe"/>
</appSettings>
</configuration>
using System.Configuration;
enjoy)
string name = ConfigurationManager.AppSettings["name"];
BTW: Do not add an app.config for a library
I found the answer in this link https://stackoverflow.com/a/1836938/1492229
It's not only necessary to use the namespace System.Configuration. You have also to add the reference to the assembly System.Configuration.dll , by
Right-click on the References / Dependencies
Choose Add Reference
Find and add System.Configuration.
This will work for sure.
Also for the NameValueCollection you have to write:
using System.Collections.Specialized;
Here's an example: App.config
<applicationSettings>
<MyApp.My.MySettings>
<setting name="Printer" serializeAs="String">
<value>1234 </value>
</setting>
</MyApp.My.MySettings>
</applicationSettings>
Dim strPrinterName as string = My.settings.Printer
Let's say I have the following in my config:
<configSections>
<section name="interestingThings" type="Test.InterestingThingsSection, Test" />
<section name="moreInterestingThings" type="Test.InterestingThingsSection, Test" />
</configSections>
<interestingThings>
<add name="Thing1" value="Seuss" />
</interestingThings>
<moreInterestingThings>
<add name="Thing2" value="Seuss" />
</moreInterestingThings>
If I want to get either section, I can get them by name pretty easily:
InterestingThingsSection interesting = (InterestingThingsSection)ConfigurationManager.GetSection("interestingThings");
InterestingThingsSection more = (InterestingThingsSection)ConfigurationManager.GetSection("moreInterestingThings");
However, this relies on my code knowing how the section is named in the config - and it could be named anything. What I'd prefer is the ability to pull all sections of type InterestingThingsSection from the config, regardless of name. How can I go about this in a flexible way (so, supports both app configs and web configs)?
EDIT: If you have the Configuration already, getting the actual sections isn't too difficult:
public static IEnumerable<T> SectionsOfType<T>(this Configuration configuration)
where T : ConfigurationSection
{
return configuration.Sections.OfType<T>().Union(
configuration.SectionGroups.SectionsOfType<T>());
}
public static IEnumerable<T> SectionsOfType<T>(this ConfigurationSectionGroupCollection collection)
where T : ConfigurationSection
{
var sections = new List<T>();
foreach (ConfigurationSectionGroup group in collection)
{
sections.AddRange(group.Sections.OfType<T>());
sections.AddRange(group.SectionGroups.SectionsOfType<T>());
}
return sections;
}
However, how do I get the Configuration instance in a generally-applicable way? Or, how do I know if I should use ConfigurationManager or WebConfigurationManager?
So far, this appears to be the best way:
var config = HostingEnvironment.IsHosted
? WebConfigurationManager.OpenWebConfiguration(null) // Web app.
: ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None); // Desktop app.
Try to use ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None) method. It opens the configuration file for the current application as a Configuration object.
MSDN documentation: https://msdn.microsoft.com/en-us/library/ms134265%28v=vs.110%29.aspx
Maybe not the best way to do it but you can read your configuration file as a normal xml and then parse the sections you want. For example if it were a web application:
XmlDocument myConfig= new XmlDocument();
myConfig.Load(Server.MapPath("~/Web.config"));
XmlNode xnodes = myConfig.SelectSingleNode("/configSections");
Now you can see the nodes that you care about discovering the names at runtime and then access the specific node of your configuration file.
Another solution is:
Path.GetFileName(AppDomain.CurrentDomain.SetupInformation.ConfigurationFile)
If this returns "web.config", it is probably a web application.
However, HostingEnvironment.IsHosted is intended to indicate whether an appdomain is configured to run under ASP.NET so it is not sure that yours is a web application.
I have made some progress on the problem I posted about yesterday, so I am rewriting the post.
My problem appears to be related to my use of generics. Here's the relevant part of App.config (formatted with whitespace for readability):
<configSections>
<section
name="NA5300ResolverSynchroDevices"
type="InfrastructureModule.DeviceConfiguration.DeviceConfigurationSection
<NA5300ResolverSynchroModule.NA5300ResolverSynchroConfigurationElement>,
NA5300ResolverSynchroModule">
</section>
</configSections>
<NA5300ResolverSynchroDevices>
<Device deviceName="AzResolverSynchro" busAddress="7"/>
<Device deviceName="ElResolverSynchro" busAddress="8"/>
</NA5300ResolverSynchroDevices>
Here's the class I'm trying to map to the configuration section:
namespace InfrastructureModule.DeviceConfiguration
{
public class DeviceConfigurationSection<T> : ConfigurationSection
where T : DeviceConfigurationElement, new()
{
[ConfigurationProperty("", IsDefaultCollection = true, IsKey = false)]
public DeviceConfigurationElementCollection<T> Devices
{
get { return (DeviceConfigurationElementCollection<T>) base[""]; }
set { base[""] = value; }
}
}
}
Here's the C# code that tries to access the config file:
DeviceConfigurationSection<NA5300ResolverSynchroConfigurationElement> devices =
ConfigurationManager.GetSection("NA5300ResolverSynchroDevices") as
DeviceConfigurationSection<NA5300ResolverSynchroConfigurationElement>;
Here's the exception text I'm getting:
An error occurred creating the configuration section handler for NA5300ResolverSynchroDevices: Could not load type 'InfrastructureModule.DeviceConfiguration.DeviceConfigurationSection<NA5300ResolverSynchroModule.NA5300ResolverSynchroConfigurationElement>' from assembly 'NA5300ResolverSynchroModule'.
I know that in C# generics are instantiated at runtime rather than at compile time (unlike C++). I do not yet know enough about generics to understand what assembly a runtime-generated type is considered to live in when the generic type and the instantiating type live in different assemblies. Above, I told the runtime to look for it in assembly NA5300ResolverSynchroModule. I've also tried telling it to look for it in assembly InfrastructureModule. Neither works.
I am attempting to use a genric type because I will have many config sections for which the corresponding ConfigurationSection-derived types will all be of the form shown above. I want to avoid code duplication.
Can anybody see why my approach is failing and how I can fix it?
Your problem is actually how you've referenced the generic type.
Instead of (shortened):
<section name="..."
type="InfrastructureModule.DeviceConfiguration.DeviceConfigurationSection
<NA5300ResolverSynchroModule.NA5300ResolverSynchroConfigurationElement>,
NA5300ResolverSynchroModule" />
Try
<section name="..."
type="InfrastructureModule.DeviceConfiguration.DeviceConfigurationSection`1[[NA5300ResolverSynchroModule.NA5300ResolverSynchroConfigurationElement, NA5300ResolverSynchroModule]],
NA5300ResolverSynchroModule" />
Note the `1[[...]] rather than <...> or <...> part for the generic type. The part inside the [[...]] can be a full type definition as well - like namespace.class,assembly,token.
The 1 is "generic type with one type parameter". If the type takes 2 "aka SomeType<T,V>", use2. Note that you should put "type, assembly" in the double square brackets, not just "type"
I believe my problem was rooted in the fact that the runtime-generated type I tried to map to a configuration section does not live in an assembly. So, I created a type that does live in an assmebly.
namespace NA5300ResolverSynchroModule
{
public class NA5300ResolverSynchroDeviceConfigurationSection :
DeviceConfigurationSection<NA5300ResolverSynchroConfigurationElement>
{
}
}
I can reference NA5300ResolverSynchroDeviceConfigurationSection just fine in App.config.
I'm trying to unit test values that will eventually wind up in a web.config file. In my test project, I created an app.config file with a web.config section to hold the settings. In a normal situation, I would call System.Configuration.ConfigurationSettings.AppSettings, but in this case, that doesn't work. I saw this question, which is very similar, but doesn't address how to get the NameValueCollection out of the config file. Here is an example of the config file:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<system.web>
<membership defaultProvider="CustomMembershipProvider">
<providers>
<clear/>
<add
name="CustomMembershipProvider"
applicationName="SettlementInfo"
enablePasswordRetrieval="false"
enablePasswordReset="false"
requiresQuestionAndAnswer="true"
writeExceptionsToEventLog="true" />
</providers>
</membership>
</system.web>
</configuration>
Has anyone dealt with this before?
I guess I'm confused here; it looks like you're trying to test that ASP.NET is using your custom membership provider appropriately. Correct?
If so, I'm 99.999% sure that you cannot unit test this using the MS framework; you must integration test it by deploying it to the webserver (or running Cassini in VS) and typing a username/password into your login page.
Now, it's possible I've misunderstood your request. If so, let me know and I'll edit my answer accordingly.
Edit:
For right now, I'm really just trying
to test the NameValue pairs coming out
of the config file, to make sure that
if the values aren't present, my
defaults are being applied. In other
words, I want to try to pull
applicationName, and verify that it
equals "SettlementInfo", and so on.
After that, I will be using
integration testing to ensure that
ASP.NET is using the custom framework
in place of the default one. Does that
make sense?
I need more than a comment to reply, so I'm editing. If I read you correctly, you are wanting to unit test your program to ensure that it deals with configuration correctly, yes? Meaning you want to ensure that your code grabs, for example, the correct AppSettings key and handles a null value therein, correct?
If that's the case, you're in luck; you don't need an app.config or web.config at all, you can set the values you need as part of your test setup.
For example:
[TestMethod]
public void Test_Configuration_Used_Correctly()
{
ConfigurationManager.AppSettings["MyConfigName"] = "MyConfigValue";
MyClass testObject = new MyClass();
testObject.ConfigurationHandler();
Assert.AreEqual(testObject.ConfigurationItemOrDefault, "MyConfigValue");
}
[TestMethod]
public void Test_Configuration_Defaults_Used_Correctly()
{
// you don't need to set AppSettings for a non-existent value...
// ConfigurationManager.AppSettings["MyConfigName"] = "MyConfigValue";
MyClass testObject = new MyClass();
testObject.ConfigurationHandler();
Assert.AreEqual(testObject.ConfigurationItemOrDefault, "MyConfigDefaultValue");
}
I believe you only have access to the webconfig file while your application is actually beeing started up. The solution is rather easy -> "Fake" your config. Use a NameValueCollection and use that instead:
private static NameValueCollection CreateConfig()
{
NameValueCollection config = new NameValueCollection();
config.Add("applicationName", "TestApp");
config.Add("enablePasswordReset", "false");
config.Add("enablePasswordRetrieval", "true");
config.Add("maxInvalidPasswordAttempts", "5");
config.Add("minRequiredNonalphanumericCharacters", "2");
config.Add("minRequiredPasswordLength", "6");
config.Add("requiresQuestionAndAnswer", "true");
config.Add("requiresUniqueEmail", "true");
config.Add("passwordAttemptWindow", "10");
return config;
}
Now you could easily pass that collection into your class that parses data from it.
You should be able to use the ConfigurationManager.GetSection() method to pull out whatever you want.
Actually, if you are using NUnit, you can stick that in an App.config in your test project.
Then add this line to your Post-build event:
copy /Y “$(ProjectDir)App.config” “$(TargetDir)$(TargetFileName).config”
When you create the new provider in your tests, NUnit will pass the values in your app.config to the provider in the initialize method.
Why not just stick it in the web.config file?