Code Snippet to Create a Checkbox List in an ASP.NET Core Razor Page Application
Checkbox lists are useful when you want to allow users to select more than one predefined option. This article explains how a Checkbox list can be generated, and the selected checkbox values can be retrieved when the page is submitted in an ASP.NET Core Razor Page application.
HTTP Error 502.5 - ANCM Out-Of-Process Startup Failure
I got the following error when I deployed my ASP.NET Core Razor page application to the production server after updating some NuGet packages to the latest version. HTTP Error 502.5 - ANCM Out-Of-Process Startup Failure
Unable to create an object of type '[DBContextName]'. For the different patterns supported at design time see https://go.microsoft.com/fwlink/?linkid=851728
You may get the following error when you run the add-migration command in EF Core 5. Unable to create an object of type '[DBContextName]'. For the different patterns supported at design time, see https://go.microsoft.com/fwlink/?linkid=851728
EF Core Migration Error: The query contains a projection '<>h_ Transparent Identifier 0 Collections in the final projection must be an 'IEnumerable<T>' type such as 'List<T>'.
The query contains a projection '<>h__TransparentIdentifier0 Collections in the final projection must be an 'IEnumerable
' type such as 'List '. Consider using 'ToList' or some other mechanism to convert the 'IQueryable ' or 'IOrderedEnumerable ' into an 'IEnumerable '.
Configure One to Many Relationship in Entity Framework Core
A one-to-many relationship is the most commonly used relationship while developing database-oriented applications. Entity Framework Core identifies one-to-many relationships based on the conventions. Fluent API can also be used to configure the relationship if the entities do not follow the conventions.
Configure One to One Relationship in Entity Framework Core
Entity Framework Core will create a one-to-one relationship when both entities involved in the relationship have a navigational property of the other and the dependant entity contains a foreign key property of the principal entity.
The entity type 'X' requires a primary key to be defined. If you intended to use a keyless entity type, call 'HasNoKey' in 'OnModelCreating'
I got the following error when I ran the add-migration command for the following entity. The entity type 'Student' requires a primary key to be defined. If you intended to use a keyless entity type,call 'HasNoKey' in 'OnModelCreating'. For more information on keyless entity types, see https://go.microsoft.com/fwlink/?linkid=2141943.
Sample Code to Create, Read, Update and Delete (CRUD) records, EF Core Many to Many relationship
This article explains how CRUD(Create, read, update, delete) operations can be performed using Entity Framework Core on tables connected through a many-to-many relationship. An asp.net core razor page application is used to demonstrate this.
Configure Many-to-Many Relationships in Entity Framework Core Code First
In RDBMS, we call a relationship between two tables many to many when more than one record in one table is associated with multiple records in the other table. In EF Core 5.0, a many to many relationship can be created without defining a joining table.
Fix: The term 'add-migration' is not recognized as the name of a cmdlet, function, script file, or operable program.
add-migration : The term 'add-migration' is not recognized as the name of a cmdlet, function, script file, or operable program.Check the spelling of the name, or if a path was included,verify that the path is correct and try again.