How to add ViewModel localization to Blazor?

Question

We all know the lack of ViewModel localization in Blazor

Today i tried many ways, and i came up with a good method to be followed to apply localization

Answer 1

DataAnnotations validation is probably not the best way to achieve this as the validation logic is tied to the class, and as you saw in your own answer, it means a lot of duplication.

FluentValidation provides an answer since it actually has built-in localization support (it also has built-in messages in many languages for default validations!).

I created a demo project on GitHub to show how it works.

As you can see this solution is a lot simpler.

Answer 2

• You can create an abstract base ViewModel for all properties for example “ProductViewModelBase“
• Then makes all of your ViewModelBase Properties as virtual

 public abstract class ProductViewModelBase
 {
               public virtual string ProductCode { get; set; }
               public virtual string ProductType { get; set; }
               public virtual string ProductName { get; set; }
 }

• Then for your ViewModel languages override any property and add your specific language message and validation rules.

  public class ProductViewModelAR : ProductViewModelBase
    {
            [Required(ErrorMessage = "خطأ")]
            public override string ProductCode { get; set; }
    }





 public class ProductViewModelEN : ProductViewModelBase
    {
            [Required(ErrorMessage = "Error")] 
            public override string ProductCode { get; set; }
    }

• In your Blazor component, check which ViewModel to load

ProductViewModelBase ViewModel;

protected override void OnInitialized()
{
    if (CultureInfo.CurrentUICulture.Name == "ar-EG")
    {
        ViewModel = new ProductViewModelAR();
    }
    else
    {
        ViewModel = new ProductViewModelEN();
    }
}

And Now you can use this ViewModel in your EditForm

<EditForm Model="ViewModel" OnValidSubmit="ValidSubmit" OnInvalidSubmit="InValidSubmit">
    <DataAnnotationsValidator />
    <ValidationSummary />

</EditForm>

And in Run-time the app will decide which ViewModel version to load based on the selected language