Required Attribute in Model

Question

User1879907140 posted

I'm using EntityFrameworkCore and created models from an existing database. Several of the tables have Required columns, however, when the model was built, the [Required] attribute doesn't appear above the column name and caused the _ValidationScriptsPartail to fail, I had to add it manually.

code generated: 

public partial class Cars
{
    public int CarId { get; set;}
    public string CarModel { get; set;}
    public string SalesPerson { get; set:}
  
}

The model and salesperson is a required field in the table,  so I had to add it manually:

public partial class Cars
{
    public int CarId { get; set;}
    [Required]
    public string CarModel { get; set;}
    [Required]
    public string SalesPerson { get; set:}
  
}

Is there something I can run to do this automatically? I don't want to add [Required] to 40 or so fields manually. 

Answer 1

User475983607 posted

There are two different types of required.   SQL has the NOT NULL constraint and MVC has input validation.  These are two different things.   I assume you used the Fluent API to set the SQL NOT NULL constraint. which is why you do not have the annotation on the entity properties 

Usually a ViewModel is used in the UI rather than an entity but whatever you choose, Entity or ViewModel, you'll need to add the [Required] attribute to the properties you wish to apply UI validation.  You might be able to scaffold the entities but I'm not sure.

Answer 2

User-474980206 posted

if not null columns have a default, then they are scaffolded as not required. if you did not supply a default, then probably, you used fluent api rather than data annotations when you scaffolded. see docs:

   https://docs.microsoft.com/en-us/ef/core/managing-schemas/scaffolding?tabs=dotnet-core-cli

-- bruce

Answer 3

User1686398519 posted

Hi,GeorgeTheCoder

• EF and ASP.NET MVC are two different things. If you want to use MVC data validation, you still need to add data annotations yourself after you generate the model.
• I found an extension tool called "Huagati DBML/EDMX Tools", which can meet your needs, you can refer to this link.

Best Regards,

YihuiSun

Answer 4

User-474980206 posted

The since mvc 4, it has supported data annotations in addition to its own.

Answer 5

User-857013053 posted

The validation attributes specify behavior that you want to enforce on the model properties they are applied to. The Required attribute indicates that a property must have a value;