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Blazor gets a Microsoft.Data.SqlClient error

I'm using a clear architecture for a NET7 project with Blazor. In the Persistence layer, I have a function to register the database and all the repositories
public static class PersistenceServiceRegistration
{
public static IServiceCollection AddPersistenceServices(
this IServiceCollection services,
IConfiguration configuration,
string cnnStringName = "LIUContextConnection")
{
var cnnString = configuration.GetConnectionString(cnnStringName);
services.AddDbContext<LIUContext>(options =>
options.UseSqlServer(cnnString)
);
services.AddScoped<IArticleRepository, ArticleRepository>();
return services;
}
}
So, in the Program.cs I can register the persistence like
builder.Services.AddPersistenceServices(builder.Configuration);
I want to be sure that the database is created before the application starts. I added the following code an the end of the Program.cs
var app = builder.Build();
LIUContext dbcontext = app.Services.GetRequiredService<LIUContext>();
dbcontext.Database.EnsureCreated();
await app.RunAsync();
When I run the application, I get an error because
Microsoft.Data.SqlClient is not supported on this platform
I added in the Client project and in the Persistence project the NuGet package but I get the some error.
If I create the database from the Package Manager Console is working.

"is not supported on this platform" is of course the main point.
The platform here is dotnet in the Browser and a lot of APIs are not (cannot be) supported. The SqlClient needs sockets and they are not allowed in the browser. Also, you wouldn't be able to keep the credentials secret.
There is some limited support for SqLite and you have the built-in IndexedDb.
For a full SQL Db, the common approach is to use a WebService (Blazor Wasm Hosted template) to handle the Db access.

AddDbContext does not get initialized when running ASP.NET Web API

I'm in the process of building a user management microservice using an API.NET Web API. I've added EntityFrameworkCore and using SQL Server as the database. I've made multiple services at this point, but this service does not seem to work the way I want it to.
FYI I'm using .NET 6.
The code you see below is how I add the AddDbContext to my Services in the Program.cs file.
builder.Services.AddDbContext<AppDbContext>(opt =>
{
// Getting the ConnectionString from the AppSettings-file.
string connectionString = builder.Configuration.GetConnectionString("Connection1");
Console.WriteLine("=====CONNECTION STRING=====");
Console.WriteLine("ConnectionString: " + connectionString + "\n");
Console.WriteLine("=====IT Asset Management=====");
Console.WriteLine("Service running: User Service");
if (builder.Environment.IsProduction())
Console.WriteLine("Environment is: PRODUCTION");
else
Console.WriteLine("Environment is: DEVELOPMENT");
// Configuring the DBContext to connect to the SQL server.
opt.UseSqlServer(connectionString);
});
When i run the code, my Console.WriteLines does not print, and it does not seem that the AddDbContext service gets initialized.
Below is my DbContext.
using Microsoft.AspNetCore.Identity.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore;
using UserService.Models;
namespace UserService.Data
{
public class AppDbContext : IdentityDbContext<AppUser>
{
public AppDbContext(DbContextOptions<AppDbContext> options)
: base(options) { }
}
}
As of now I have tried everything I can think of and gotten help from colleagues, but we can't seem to find out what's wrong. I have another service running the exact same code, but with a different purpose (Only the Program.cs files are the same), so I've tried to copy paste the file. I have tried to reinstall all the related NuGet-packages, which did not work.
Then i tried to create a new ASP.NET Web API project and only installing the packages needed to make the DbContext and setup the service in the Program.cs file. Below is the Program.cs file from the new project.
The funny thing is that it does not work aswell in the new project and I have no idea why.
using UserManagement.Data;
var builder = WebApplication.CreateBuilder(args);
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
builder.Services.AddDbContext<AppDbContext>(opt =>
{
Console.WriteLine("=====IT Asset Management=====");
Console.WriteLine("Service running: User Service");
});
var app = builder.Build();
if (app.Environment.IsDevelopment())
{
app.UseSwagger();
app.UseSwaggerUI();
}
app.UseHttpsRedirection();
app.UseAuthorization();
app.MapControllers();
app.Run();
I cannot think of anything I have done differently between these three projects.
UPDATE 1:
I found this post: AddDbContext doesn't call DbContext constructor
and one of the answers was that I needed to use migrations. I have not migrated anything from this project, since there is no tables to be made. I am using the default Identity tables, and they are created by another service. But when I added the migrations the Console.WriteLines got printed. Then i ran the project with "dotnet run" but then the prints were gone. Why is this?

So I seemed that one of the answers inside the post in UPDATE 1, actually was the solution to the issue. I did indeed have to use the DbContext in some context. I added a dataseeding class which is called from the program.cs file, and it seems that the console.writelines are printed every time now.

Visual Studio: Connect MySQL database running on localhost to ASP.NET project

I am currently trying to teach myself ASP.NET, as I will need it on the job soon. For testing purpose, I want to create a simple project with 1 or 2 RazorPages, which derives data from a MySQL database on my localhost. I am using the Visual Studio Community version. I started by creating a new ASP.NET Core Web Application project, then added a "New Connection" (see screenshot)
I also installed the packages "MySqlData", "MySqlData.EntityFrameworkCore" and "MySQLConnector". In appsettings.json, I added
"ConnectionStrings": {
"RazorPagesPlayersContext": "server=localhost;user=root;password=password;database=players;"
}
and in Startup.cs, I configured
public void ConfigureServices(IServiceCollection services)
{
services.AddRazorPages();
services.AddDbContext<RazorPagesPlayersContext>(options => options.UseSqlite(Configuration.GetConnectionString("RazorPagesPlayersContext")));
}
However, when I to go to the create page and post a new "player" into the database, I am getting error
ArgumentException: Connection string keyword 'server' is not supported
My context file looks like this
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;
using RazorPagesPlayers.Models;
namespace RazorPagesPlayers.Data
{
public class RazorPagesPlayersContext : DbContext
{
public RazorPagesPlayersContext (DbContextOptions<RazorPagesPlayersContext> options)
: base(options)
{
}
public DbSet<RazorPagesPlayers.Models.Player> Player { get; set; }
}
}
When I check "Connected Services", I can only see this
I can see, that the connection string of this service has nothing to do with the connection string I added in appsettings.json. When I try to change it, it will just switch back. So I am guessing the connection to MySQL failed or am I confusing things here? I am not even sure if I am looking in the right direction, but every hint would be most welcome. Thank you very much in advance
Edit: When I change the Service config in Startup.cs to
services.AddDbContext<RazorPagesPlayersContext>(options => options.UseMySql(Configuration.GetConnectionString("RazorPagesPlayersContext")));
it tells me "DbContextOptionsBuilder" does not contains a defintion for 'UseMySql' and recommends to change it to UseMySQL. This however results in an error:
TypeLoadException: Method 'Create' in type 'MySql.Data.EntityFrameworkCore.Query.Internal.MySQLSqlTranslatingExpressionVisitorFactory' from assembly 'MySql.Data.EntityFrameworkCore, Version=8.0.22.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' does not have an implementation.
is there a point in installing Pomelo?

When I run my ASP.NET Core MVC solution from another user it does not connect to the SQL Server database

I have created a simple ASP.NET Core MVC application in Visual Studio. I also created a database using EF Core code first approach. The database uses Windows authentication.
The connection string I used was
Server=(local)\\sqlexpress;Database=LibraryEmployeeDB;Trusted_Connection=True;
I am supposed to send this project to my professor but when I tried to run the project from a different user on my computer it doesn’t work because I can’t connect to the database with the other user.
I tried to change to Windows and SQL Server authentication and create a new user and add that to the connection string but that didn’t work either. I would be so grateful for any tips on how to solve this problem so that my professor can run the project as it is supposed to. Thank you!

You should run init command to create the database :
"Update-Database" in the Package manager console in the Visual studio.

Your Connection String shulde be like this:
"ConnectionStrings": {
"ConnStr": "Data Source=(local)\\sqlexpress;Initial Catalog=LibraryEmployeeDB;Integrated Security=False;ApplicationIntent=ReadWrite;MultiSubnetFailover=False;Trusted_Connection=false;User ID=yourUsername;Password=yourPassword;"
}
and in Startup.cs you have to use this section:
public void ConfigureServices(IServiceCollection services)
{
services.AddDbContext<YourContext>(options => options.UseSqlServer(Configuration.GetConnectionString("ConnStr")));
//and other things
}

Share Sqlite database between asp.net core project and .net core console project with a third data class library project

I have 3 projects in a vs2019 solution which should use the same sqlite database using Entity Framework Core.
First project: an .net core class library with all database models, database context, database repositories and migrations.
Second project: an .net core console application which needs to scan files, retrieve metadata from inet and seed the database with retrieved content. This is done by referencing the first project and use the repositories to access the database.
Third project: an Asp.net core Webapi which need to accept client requests for retrieving, updating, etc data from the same database. This is also done by referencing the first project and using the repositories. This project is the main project and needs to start the second project when needed.
All projects need to be able to get installed on client machines targeting Windows, MacOS and Linux. And be self hosted. It has to act like a content server simular to Plex, Emby and Calibre.
My problem is how to create the datasource option string to be able to use the same db file and have that file copied to the location of the Asp.net core Webapi project.
I now have this in my dbcontext file at the first project:
public class ApplicationDbContext : DbContext
{
public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options) : base(options) { }
#region DbSets
public DbSet<Authors> Authors { get; set; }
...
...
public class DesignTimeDbContextFactory : IDesignTimeDbContextFactory<ApplicationDbContext>
{
public ApplicationDbContext CreateDbContext(string[] args)
{
var builder = new DbContextOptionsBuilder<ApplicationDbContext>();
builder.UseSqlite("Data Source=Chapter.db");
return new ApplicationDbContext(builder.Options);
}
}
And this in my repository class in the first project:
public class GenericRepository<T> : IGenericRepository<T> where T : class
{
private DbContextOptionsBuilder<ApplicationDbContext> _optionsBuilder;
public ApplicationDbContext _context = null;
public DbSet<T> table = null;
public GenericRepository()
{
_optionsBuilder = new DbContextOptionsBuilder<ApplicationDbContext>().UseSqlite("Data Source=Chapter.db");
this._context = new ApplicationDbContext(_optionsBuilder.Options);
table = _context.Set<T>();
}
When I use entity framework to create the database from the migrations in the first project, it creates the Chapter.db file in the main folder of the first project.
In my Asp.net Webapi project i have this to use the database:
public void ConfigureServices(IServiceCollection services)
{
services.AddDbContext<ApplicationDbContext>(options =>
options.UseSqlite("Data Source=Chapter.db"));
Do i need this line of code or can i use the repository classes from the first project?
When I build the solution I have all the projects their dll's in the debug folder of the third project but not the chapter.db database file.
How do you copy the db file automaticly in the correct projects output directories when building for debug and release?
And what do I need to use for the Datasource= connection string to be sure that after people install the application it targets the db file (in windows, linux and macos)?
I have read two answers from simular questions to use:
Var SqlitePath = Path.combine(
Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
#"<YourAppName>\Chapter.db");
And:
var builder = new SqliteConnectionStringBuilder(connectionString);
builder.DataSource = Path.GetFullPath( Path.Combine(
AppDomain.CurrentDomain.GetData("DataDirectory") as string ?
AppDomain.CurrentDomain.BaseDirectory, builder.DataSource);
connectionString = builder.ToString();
Are these answers having the same outcome? And am I able to use one of these in the asp.net core project aswell as in the .net core console application?
And does that work cross-platform?

I'm a bit late and I'm assuming that you have already figured this out, but I'm writing this answer since it was a top result to one of my google searches.
The issue at hand is pointing to the correct location of the database.
public void ConfigureServices(IServiceCollection services)
{
services.AddDbContext<ApplicationDbContext>(options =>
options.UseSqlite("Data Source=Chapter.db"));
This line of code will be creating a database called "Chapter.db" within the project directory of whichever project you are running it in. The solution to the problem was provided at the bottom of your question.
Var SqlitePath = Path.combine(
Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
#"<YourAppName>\Chapter.db");
This code will convert the relative path to the database (based on the project directory) to an absolute path (one based on your file system instead, i.e. C:...\Chapter.db or /home/.../Chapter.db). The other blob you provided should do the same thing, but with more lines of code. After reading SqliteConnectionStringBuilder documentation it seems that the later has more functionality allowing for passwords and other fun stuff to be added through code rather than manually put through a string.
Absolute pathing will help out in this scenario as it will allow for you to specify a direct path to the database file you are using. Otherwise, you would need to modify the connection string to use relative pathing for each of your projects which could become complex if they were to ever move to different parts of your file system. It can still be done. For example if both projects are in the same location, appending "../" in front of your database name would suffice in providing the same location to all of your projects.
Using absolute pathing, you could just specify a location like "C:\Chapter.db" and all of your projects would use the database at that location rather than their individual files.