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Dependency Injection how to re-add all services to builder.Services after config change

This question is specific to NET Maui in my case.
My Settings file:
{
"MyConfig": {
"FactoryConfig1": {
"SomeType1": "SomeConfig1"
},
"FactoryConfig2": {
"SomeType2": "SomeConfig2"
}
}
}
Let's say I'm creating my services like this:
var builder = MauiApp.CreateBuilder();
builder.Services.AddSingleton<IService1, Service1>();
builder.Services.AddSingleton<IService2, Service2>();
builder.Services.AddTransient<Service3>();
// and config file-- how to modify this to use IOptions to use with IOptions Monitor?
var a = Assembly.GetExecutingAssembly();
using var stream = a.GetManifestResourceStream("MauiBlazorTestApp.appsettings.json");
var config = new ConfigurationBuilder()
.AddJsonStream(stream)
.Build();
builder.Configuration.AddConfiguration(config);
return builder.Build();
then in another class I get the config:
public class Service1 : IService1
{
IConfiguration _configuration;
public Service1(IConfiguration configuration)
{
_configuration = configuration;
}
public void SomeMethod()
{
var myConfig = _configuration.GetRequiredSection("MyConfig").Get<MyConfig>();
}
}
In each of the services, I'm injecting an IConfiguration with the configuration parameters used in each service from an appsettings.json file.
The code above works the way it is but what if sometime after starting the app, and after the services have been already created with the existing settings, the user changes some settings in appsettings.json from a UI dashboard page, how can I reload all those services with the new config settings for each...
I have to clear the services, and re-add them, is this possible, in a class outside program.cs?
It would work if I restart the application, but can it be done without, just a refresh of the DI?

As #Nkosi mentioned in the comments you should always use option pattern and not directly access the IConfiguration object.
In your case just use a class to store the desired values from configuration:
public class MyConfig
{
// The class to bind IConfiguration to
public string YourSetting { get; set; }
}
add options to the service collection and configure them. Also note the reloadOnChange parameter used during setup which indicates whether the configuration is reloaded if the file changes.
//...
builder.Configuration
.AddJsonFile("MauiBlazorTestApp.appsettings.json", optional: false, reloadOnChange: true);
// Add and configure your options
builder.Services.AddOptions();
builder.Services.Configure<MyConfig>(builder.Configuration.GetRequiredSection("MyConfig"));
//...
and finally inject the options into the target services and access the settings as needed.
public class Service1 : IService1
{
private readonly IOptionsMonitor<MyConfig> _options;
public Service1(IOptionsMonitor<MyConfig> options)
{
_options = options;
}
public void SomeMethod()
{
// Read the current value provided via IConfiguration
MyConfig appSettings = _options.CurrentValue;
var value = appSettings.YourSetting;
//...use setting as needed
}
}
When ever the current setting is requested, it will pull the latest version from settings, even if the service is a singeton.
For more information you can find this pattern very well documented here and especially for the IOptionsMonitor here

How do I add code that was previously in Startup.cs -->Configure method when using Azure Functions v3 in .NET 5 isolated process

I am working with a new C# Function App using the .NET 5 dotnet-isolated where the examples only show the Program.cs and there is no Startup.cs class. I have an issue where I need to register a SyncFusion license, which I typically do in the Startup.cs -->Configure Method by using this line;
Syncfusion.Licensing.SyncfusionLicenseProvider.RegisterLicense("...");
But I do not know where to add this line in the new approach in a .NET 5 isolated process function where there is no Startup.cs file.
Can anyone provide an example of where I would add things I would typically put in a Startup.cs --> Configure method?
Is there some extension method you can daisy chain similar to the...
.ConfigureServices(services =>
{
...
...
...
}
... used with the HostBuilder in the .NET 5 isolated process version of the program.cs file?

Option 1
I would follow the existing pattern and create an extension method to IServiceCollection in the appropriate project, like this:
public static class ServiceCollectionExtensions
{
public static void AddLicense(this IServiceCollection services)
{
Syncfusion.Licensing.SyncfusionLicenseProvider.RegisterLicense("...");
}
}
Then, in the program.cs file of your Function project, you can call it like that:
static Task Main(string args[])
{
var hostBuilder = new HostBuilder()
...
.ConfigureServices(services =>
{
services.AddLicense();
});
}
Option 2
Now, it is possible you may need more information to register the actual license. Let's say it is a serial number; it might not be a good idea to hard code it. Instead, we put it in a configuration (which could be even be linked to a key vault for better security).
First, let's define our configuration class:
public class LicenseConfiguration
{
// I chose a serial number by it could be something else.
public string SerialNumber { get; set;}
}
Now, you could define an IHostedService that would run every time your function starts:
public class LicenseRegistrationService : IHostedService
{
private readonly LicenseConfiguration _licenseConfiguration;
public LicenseRegistrationService(IOptions<LicenseConfiguration> licenseConfiguration)
{
_licenseConfiguration = licenseConfiguration.Value;
}
public Task StartAsync(CancellationToken cancellationToken)
{
Syncfusion.Licensing.SyncfusionLicenseProvider.RegisterLicense(_licenseConfiguration.SerialNumber);
return Task.CompletedTask;
}
public Task StopAsync(CancellationToken cancellationToken)
{
return Task.CompletedTask;
}
}
Now let's hook everything up in the Program class:
static Task Main(string args[])
{
var hostBuilder = new HostBuilder()
...
.ConfigureServices(services =>
{
// Register you hosted service
services.AddHostedService<LicenseRegistrationService >();
// Bind your configuration parameters
services.AddOptions<LicenseConfiguration>()
.Configure<IConfiguration>((settings, configuration) =>
{
configuration.GetSection(nameof(LicenseConfiguration)).Bind(settings);
});
});
}
In your local.settings.json file, you can put the proper configuration to validate everything locally:
{
"IsEncrypted": false,
"Values": {
...
"LicenseConfiguration__SerialNumber": "this-is-your-serial-number"
}
}

How do I access my configuration from within a static function in .Net Core 2.1?

I am creating an Azure web job in .Net Core 2.1 (via a "console" app in Visual Studio). In this project, I have a static function that reads messages from a queue. Within this function, I need to use connection strings (from my configuration) to write to a database. This is my setup:
Program.cs
class Program
{
static void Main(string[] args)
{
var builder = new HostBuilder();
builder.ConfigureWebJobs(b =>
{
b.AddAzureStorageCoreServices();
b.AddAzureStorage();
});
builder.ConfigureAppConfiguration((hostContext, config) =>
{
var conf = new ConfigurationBuilder()
.AddJsonFile("appsettings.json", optional: false, reloadOnChange: true).Build();
config.AddConfiguration(conf);
config.AddEnvironmentVariables();
})
builder.ConfigureLogging((context, b) =>
{
b.AddConsole();
});
var host = builder.Build();
using (host)
{
host.Run();
}
}
}
Functions.cs
public class Functions
{
public static void ProcessQueueMessage([QueueTrigger("myqueue")] string message, ILogger logger, IConfiguration configuration)
{
logger.LogInformation(message);
logger.LogInformation(configuration.GetConnectionString("MyDatabase"));
}
}
appsettings.json
{
"ConnectionStrings": {
"MyDatabase": "foo",
"AzureWebJobsDashboard": "foo2",
"AzureWebJobsStorage": "foo3"
}
}
However, when I run this, I get the following error:
Error indexing method 'Functions.ProcessQueueMessage'
Cannot bind parameter 'configuration' to type IConfiguration. Make
sure the parameter Type is supported by the binding. If you're using
binding extensions (e.g. Azure Storage, ServiceBus, Timers, etc.) make
sure you've called the registration method for the extension(s) in
your startup code (e.g. builder.AddAzureStorage(),
builder.AddServiceBus(), builder.AddTimers(), etc.).
I am very new to .Net Core, especially the DI pattern. And I believe that is the issue. I also see many examples of how to implement and use the configuration from within the Main function, but not from within a static helper function like this. How do I properly implement my configuration from within my static function?

Consider changing the approach and not try to inject IConfiguration.
Create a class to hold your desired settings
public class MyOptions {
public string MyDatabase { get; set; }
}
Refactor the setup to also use ConfigureServices and extract the desired configuration to populate the settings object and add it to the service collection
var builder = new HostBuilder();
builder
.ConfigureWebJobs(b => {
b.AddAzureStorageCoreServices();
b.AddAzureStorage();
})
.ConfigureAppConfiguration(config => { //not using context so no need for it really
config.AddJsonFile("appsettings.json", optional: false, reloadOnChange: true).Build();
config.AddEnvironmentVariables();
})
//...ADDITION HERE
.ConfigureServices((context, services) => {
//Configuration should be available by now, so access what you need.
var connectionString = context.Configuration.GetConnectionString("MyDatabase");
//If null you have the option to fail early, otherwise carry on.
var myOptions = new MyOptions {
MyDatabase = connectionString,
};
services.AddSingleton(myOptions);
}
.ConfigureLogging((context, b) => {
b.AddConsole();
});
//...
That way at this point you should be able to add your object as a dependency to the function
public class Functions {
public static void ProcessQueueMessage(
[QueueTrigger("myqueue")] string message,
ILogger logger,
MyOptions options) {
logger.LogInformation(message);
logger.LogInformation(options.MyDatabase);
}
}
I personally believe trying to access IConfiguration outside of startup to be more trouble than its worth and would even rank it with service locator anti-pattern and injecting IServiceProvider. Get what you need from it during setup, register that with service collection so it's available for injection where needed explicitly.

Configure a dbContext from a webjob

I have a website that takes input from emails that go out to users (an email is sent to everyone, they click a link which calls a controller action). I want to use a webjob to send the emails out, but I need to cycle through all the users in the database to grab the email addresses.
I set up the website and everything is working great. I have the DbContext inheriting from IdentityDbContext here:
public class MooodDbContext : IdentityDbContext<ApplicationUser>
{
public MooodDbContext(DbContextOptions options) : base(options)
{
}
public DbSet<Response> Response { get; set; }
public DbSet<Cow> Cow { get; set; }
public DbSet<Herd> Herd { get; set; }
}
The ConfigureServices is run when I launch the webapp
public void ConfigureServices(IServiceCollection services)
{
// Add framework services.
services.AddDbContext<MooodDbContext>(options =>
options.UseSqlServer(Configuration.GetConnectionString("MooodConnection")));
services.AddIdentity<ApplicationUser, IdentityRole>()
.AddEntityFrameworkStores<MooodDbContext>()
.AddDefaultTokenProviders();
services.AddMvc(options => options.Filters.Add(typeof(UnauthorizedExceptionFilterAttribute)));
services.AddScoped<IDbInitializer, DbInitializer>();
// Add application services.
services.AddTransient<IEmailSender, AuthMessageSender>();
services.AddTransient<ISmsSender, AuthMessageSender>();
}
but obviously not when I run the webjob. So, when I try to access anything in the context, I get this exception (after setting context = new context()):
System.InvalidOperationException occurred
HResult=0x80131509
Message=No database provider has been configured for this DbContext. A provider can be configured by overriding the DbContext.OnConfiguring method or by using AddDbContext on the application service provider. If AddDbContext is used, then also ensure that your DbContext type accepts a DbContextOptions<TContext> object in its constructor and passes it to the base constructor for DbContext.
Source=Microsoft.EntityFrameworkCore
It seems to me, it's because I'm not doing any configuration on the DbContext, but I'm not sure. Is there a better way to accomplish this? Or am I missing something small?
Edit: This is the program.cs of my webjob (minus the emailing functionality, which is cluttery):
private static MooodDbContext _context;
// Please set the following connection strings in app.config for this WebJob to run:
// AzureWebJobsDashboard and AzureWebJobsStorage
private static void Main()
{
_context = new MooodDbContext(new DbContextOptions<MooodDbContext>());
var host = new JobHost();
EmailAllHerds();
host.RunAndBlock();
EmailAllHerds();
}

Couple of assumptions that i made here
web job is a console App built on .net core
So you will have Program.cs file with a main method. So in your
Program.cs
class Program {
// declare a field to store config values
private readonly IConfigurationRoot _configuration;
// Declare a constructor
public Program()
{
var builder = new ConfigurationBuilder()
.SetBasePath(environment.BasePath)
.AddJsonFile($"appsettings.json", true, true)
.AddJsonFile($"appsettings.{environment.EnvironmentName}.json", true, true)
.AddEnvironmentVariables();
_configuration = builder.Build();
}
}
public static void Main(string[] args)
{
var program = new Program();
var serviceCollection = new ServiceCollection();
program.ConfigureServices(serviceCollection);
}
private void ConfigureServices(IServiceCollection services)
{
// now here you can resolve your DbContext similar to web
services.AddDbContext<MooodDbContext>(options =>options.UseSqlServer(_configuration.GetConnectionString("MooodConnection")));
}
}

How do I access Configuration in any class in ASP.NET Core?

I have gone through configuration documentation on ASP.NET core. Documentation says you can access configuration from anywhere in the application.
Below is Startup.cs created by template
public class Startup
{
public Startup(IHostingEnvironment env)
{
var builder = new ConfigurationBuilder()
.SetBasePath(env.ContentRootPath)
.AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
.AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true);
if (env.IsEnvironment("Development"))
{
// This will push telemetry data through Application Insights pipeline faster, allowing you to view results immediately.
builder.AddApplicationInsightsSettings(developerMode: true);
}
builder.AddEnvironmentVariables();
Configuration = builder.Build();
}
public IConfigurationRoot Configuration { get; }
// This method gets called by the runtime. Use this method to add services to the container
public void ConfigureServices(IServiceCollection services)
{
// Add framework services.
services.AddApplicationInsightsTelemetry(Configuration);
services.AddMvc();
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline
public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
loggerFactory.AddConsole(Configuration.GetSection("Logging"));
loggerFactory.AddDebug();
app.UseApplicationInsightsRequestTelemetry();
app.UseApplicationInsightsExceptionTelemetry();
app.UseMvc();
}
}
So in Startup.cs we configure all the settings, Startup.cs also has a property named Configuration
What I'm not able to understand how do you access this configuration in controller or anywhere in the application? MS is recommending to use options pattern but I have only 4-5 key-value pairs so I would like not to use options pattern. I just wanted to have access to Configuration in application. How do I inject it in any class?

Update
Using ASP.NET Core 2.0 will automatically add the IConfiguration instance of your application in the dependency injection container. This also works in conjunction with ConfigureAppConfiguration on the WebHostBuilder.
For example:
public static void Main(string[] args)
{
var host = WebHost.CreateDefaultBuilder(args)
.ConfigureAppConfiguration(builder =>
{
builder.AddIniFile("foo.ini");
})
.UseStartup<Startup>()
.Build();
host.Run();
}
It's just as easy as adding the IConfiguration instance to the service collection as a singleton object in ConfigureServices:
public void ConfigureServices(IServiceCollection services)
{
services.AddSingleton<IConfiguration>(Configuration);
// ...
}
Where Configuration is the instance in your Startup class.
This allows you to inject IConfiguration in any controller or service:
public class HomeController
{
public HomeController(IConfiguration configuration)
{
// Use IConfiguration instance
}
}

The right way to do it:
In .NET Core you can inject the IConfiguration as a parameter into your Class constructor, and it will be available.
public class MyClass
{
private IConfiguration configuration;
public MyClass(IConfiguration configuration)
{
ConnectionString = new configuration.GetValue<string>("ConnectionString");
}
Now, when you want to create an instance of your class, since your class gets injected the IConfiguration, you won't be able to just do new MyClass(), because it needs a IConfiguration parameter injected into the constructor, so, you will need to inject your class as well to the injecting chain, which means two simple steps:
1) Add your Class/es - where you want to use the IConfiguration, to the IServiceCollection at the ConfigureServices() method in Startup.cs
services.AddTransient<MyClass>();
2) Define an instance - let's say in the Controller, and inject it using the constructor:
public class MyController : ControllerBase
{
private MyClass _myClass;
public MyController(MyClass myClass)
{
_myClass = myClass;
}
Now you should be able to enjoy your _myClass.configuration freely...
Another option:
If you are still looking for a way to have it available without having to inject the classes into the controller, then you can store it in a static class, which you will configure in the Startup.cs, something like:
public static class MyAppData
{
public static IConfiguration Configuration;
}
And your Startup constructor should look like this:
public Startup(IConfiguration configuration)
{
Configuration = configuration;
MyAppData.Configuration = configuration;
}
Then use MyAppData.Configuration anywhere in your program.
Don't confront me why the first option is the right way, I can just see experienced developers always avoid garbage data along their way, and it's well understood that it's not the best practice to have loads of data available in memory all the time, neither is it good for performance and nor for development, and perhaps it's also more secure to only have with you what you need.

I know this is old but given the IOptions patterns is relatively simple to implement:
Class with public get/set properties that match the settings in the configuration
public class ApplicationSettings
{
public string UrlBasePath { get; set; }
}
register your settings
public void ConfigureServices(IServiceCollection services)
{
...
services.Configure<ApplicationSettings>(Configuration.GetSection("ApplicationSettings"));
...
}
inject via IOptions
public class HomeController
{
public HomeController(IOptions<ApplicationSettings> appSettings)
{ ...
appSettings.Value.UrlBasePath
...
// or better practice create a readonly private reference
}
}
I'm not sure why you wouldn't just do this.

There is also an option to make configuration static in startup.cs so that what you can access it anywhere with ease, static variables are convenient huh!
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
internal static IConfiguration Configuration { get; private set; }
This makes configuration accessible anywhere using Startup.Configuration.GetSection... What can go wrong?

I'm doing it like this at the moment:
// Requires NuGet package Microsoft.Extensions.Configuration.Json
using Microsoft.Extensions.Configuration;
using System.IO;
namespace ImagesToMssql.AppsettingsJson
{
public static class AppSettingsJson
{
public static IConfigurationRoot GetAppSettings()
{
string applicationExeDirectory = ApplicationExeDirectory();
var builder = new ConfigurationBuilder()
.SetBasePath(applicationExeDirectory)
.AddJsonFile("appsettings.json");
return builder.Build();
}
private static string ApplicationExeDirectory()
{
var location = System.Reflection.Assembly.GetExecutingAssembly().Location;
var appRoot = Path.GetDirectoryName(location);
return appRoot;
}
}
}
And then I use this where I need to get the data from the appsettings.json file:
var appSettingsJson = AppSettingsJson.GetAppSettings();
// appSettingsJson["keyName"]

I know there may be several ways to do this, I'm using Core 3.1 and was looking for the optimal/cleaner option and I ended up doing this:
My startup class is as default
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
public IConfiguration Configuration { get; }
// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
services.AddControllers();
}
My appsettings.json is like this
{
"CompanySettings": {
"name": "Fake Co"
}
}
My class is an API Controller, so first I added the using reference and then injected the IConfiguration interface
using Microsoft.Extensions.Configuration;
public class EmployeeController
{
private IConfiguration _configuration;
public EmployeeController(IConfiguration configuration)
{
_configuration = configuration;
}
}
Finally I used the GetValue method
public async Task<IActionResult> Post([FromBody] EmployeeModel form)
{
var companyName = configuration.GetValue<string>("CompanySettings:name");
// companyName = "Fake Co"
}

I looked into the options pattern sample and saw this:
public class Startup
{
public Startup(IConfiguration config)
{
// Configuration from appsettings.json has already been loaded by
// CreateDefaultBuilder on WebHost in Program.cs. Use DI to load
// the configuration into the Configuration property.
Configuration = config;
}
...
}
When adding Iconfiguration in the constructor of my class, I could access the configuration options through DI.
Example:
public class MyClass{
private Iconfiguration _config;
public MyClass(Iconfiguration config){
_config = config;
}
... // access _config["myAppSetting"] anywhere in this class
}

In 8-2017 Microsoft came out with System.Configuration for .NET CORE v4.4. Currently v4.5 and v4.6 preview.
For those of us, who works on transformation from .Net Framework to CORE, this is essential. It allows to keep and use current app.config files, which can be accessed from any assembly. It is probably even can be an alternative to appsettings.json, since Microsoft realized the need for it. It works same as before in FW. There is one difference:
In the web applications, [e.g. ASP.NET CORE WEB API] you need to use app.config and not web.config for your appSettings or configurationSection. You might need to use web.config but only if you deploying your site via IIS. You place IIS-specific settings into web.config
I've tested it with netstandard20 DLL and Asp.net Core Web Api and it is all working.

Using the Options pattern in ASP.NET Core is the way to go. I just want to add, if you need to access the options within your startup.cs, I recommend to do it this way:
CosmosDbOptions.cs:
public class CosmosDbOptions
{
public string ConnectionString { get; set; }
}
Startup.cs:
public void ConfigureServices(IServiceCollection services)
{
// This is how you can access the Connection String:
var connectionString = Configuration.GetSection(nameof(CosmosDbOptions))[nameof(CosmosDbOptions.ConnectionString)];
}

I have to read own parameters by startup.
That has to be there before the WebHost is started (as I need the “to listen” url/IP and port from the parameter file and apply it to the WebHost). Further, I need the settings public in the whole application.
After searching for a while (no complete example found, only snippets) and after various try-and-error's, I have decided to do it the “old way" with an own .ini file.
So.. if you want to use your own .ini file and/or set the "to listen url/IP" your own and/or need the settings public, this is for you...
Complete example, valid for core 2.1 (mvc):
Create an .ini-file - example:
[Startup]
URL=http://172.16.1.201:22222
[Parameter]
*Dummy1=gew7623
Dummy1=true
Dummy2=1
whereby the Dummyx are only included as example for other date types than string (and also to test the case “wrong param” (see code below).
Added a code file in the root of the project, to store the global variables:
namespace MatrixGuide
{
public static class GV
{
// In this class all gobals are defined
static string _cURL;
public static string cURL // URL (IP + Port) on that the application has to listen
{
get { return _cURL; }
set { _cURL = value; }
}
static bool _bdummy1;
public static bool bdummy1 //
{
get { return _bdummy1; }
set { _bdummy1 = value; }
}
static int _idummy1;
public static int idummy1 //
{
get { return _idummy1; }
set { _idummy1 = value; }
}
static bool _bFehler_Ini;
public static bool bFehler_Ini //
{
get { return _bFehler_Ini; }
set { _bFehler_Ini = value; }
}
// add further GV variables here..
}
// Add further classes here...
}
Changed the code in program.cs (before CreateWebHostBuilder()):
namespace MatrixGuide
{
public class Program
{
public static void Main(string[] args)
{
// Read .ini file and overtake the contend in globale
// Do it in an try-catch to be able to react to errors
GV.bFehler_Ini = false;
try
{
var iniconfig = new ConfigurationBuilder()
.SetBasePath(Directory.GetCurrentDirectory())
.AddIniFile("matrixGuide.ini", optional: false, reloadOnChange: true)
.Build();
string cURL = iniconfig.GetValue<string>("Startup:URL");
bool bdummy1 = iniconfig.GetValue<bool>("Parameter:Dummy1");
int idummy2 = iniconfig.GetValue<int>("Parameter:Dummy2");
//
GV.cURL = cURL;
GV.bdummy1 = bdummy1;
GV.idummy1 = idummy2;
}
catch (Exception e)
{
GV.bFehler_Ini = true;
Console.ForegroundColor = ConsoleColor.Red;
Console.WriteLine("!! Fehler beim Lesen von MatrixGuide.ini !!");
Console.WriteLine("Message:" + e.Message);
if (!(e.InnerException != null))
{
Console.WriteLine("InnerException: " + e.InnerException.ToString());
}
Console.ForegroundColor = ConsoleColor.White;
}
// End .ini file processing
//
CreateWebHostBuilder(args).Build().Run();
}
public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
WebHost.CreateDefaultBuilder(args)
.UseStartup<Startup>() //;
.UseUrls(GV.cURL, "http://localhost:5000"); // set the to use URL from .ini -> no impact to IISExpress
}
}
This way:
My Application config is separated from the appsettings.json and I
have no sideeffects to fear, if MS does changes in future versions ;-)
I have my settings in global variables
I am able to set the "to listen url" for each device, the applicaton run's on (my dev machine, the intranet server and the internet server)
I'm able to deactivate settings, the old way (just set a * before)
I'm able to react, if something is wrong in the .ini file (e.g. type mismatch)
If - e.g. - a wrong type is set (e.g. the *Dummy1=gew7623 is activated instead of
the Dummy1=true) the host shows red information's on the console
(including the exception) and I' able to react also in the
application (GV.bFehler_Ini ist set to true, if there are errors with
the .ini)