.NET Framework Detection in the Windows Registry
To determine which .NET framework is installed on the Windows computer check the values in the registry. The HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full key contains two values you can check: Release Version You can use InSpec,…
Block comment in ASP.NET MVC Razor file
To comment out a block of lines in the ASP.NET MVC Razor file, enclose them in @* and *@ @* Commented out instructions, including HTML and Extension methods *@
Procedure or function ‘`…_Insert`’ cannot be found in database …
When you use the Microsoft .NET Entity framework to access a MySql database, the autogenerated code throws an error when you try to insert a row into the database with context.MY_TABLE.Add(MY_OBJECT); Server Error in ‘/’ Application.…
No connection string named ‘…’ could be found in the application config file.
Two-tier applications separate the presentation layer and the data layer, and all database access related objects are located in the data-tier. When the application runs, the config file of the main project is read. In web applications, it is the…
NotSupportedException: Unable to determine the provider name for provider factory of type ‘MySql.Data.MySqlClient.MySqlClientFactory’. Make sure that the ADO.NET provider is installed or registered in the application config
In a two-tier web application, the data layer is in a separate project. This allows better separation between the presentation layer and the data layer. This way you can reuse the data project in another application that targets the same database. To…
The given assembly name or codebase was invalid. (Exception from HRESULT: 0x80131047)
When I made changes to the web.config file of an ASP.Net C# application, I have accidentally deleted a comma, and I started to get the runtime error message: The given assembly name or codebase was invalid. (Exception from HRESULT: 0x80131047) Make sure…
Generate Entity Framework Entity Data Model in Visual Studio 2017
Visual Studio 2017 has many project type options, and not all of them support the Entity Framework user interface to generate the Entity Framework Data Model (EDMX) file. If you create an ASP.NET Web Application(.NET Framework) you can add the EDMX file…
{“error”:”Entity type ‘AspNetUserRoles’ has composite primary key defined with data annotations. To set composite primary key, use fluent API.”}
When a database table has composite keys (multiple columns are in the key) you cannot use the usual key definition [Key] [Display(Name = “UserId”)] public string UserId { get; set; } [Key] [Display(Name = “RoleId”)] public string…
Generate SQL script from Entity Framework migration script
It is not recommended to execute Entity Framework migration scripts in production, It is important that you execute all SQL steps manually on the production database section-by-section to immediately see the result and be able to recover in case a…
DbUpdateConcurrencyException: Database operation expected to affect 1 row(s) but actually affected 0 row(s). Data may have been modified or deleted since entities were loaded.
The .NET Core Entity framework makes database access easy. When you auto-generate a Razor page in a .NET web application to edit a data row, the scaffolding places controls on the page for every column. There are columns in most of the tables that we…