Question

When I add validation rules to a Model class, an error message can be added to it, however only in one language; how can I add error messages translated in more languages for a single property?
Have I to write more class “copies” or exists a better method to implement it?

Public Class Movie
    Public Property ID() As Integer

    <Required(ErrorMessage:="Title is required")>
    Public Property Title() As String

    <Required(ErrorMessage:="Date is required")>
    Public Property ReleaseDate() As Date

    <Required(ErrorMessage:="Genre must be specified")>
    Public Property Genre() As String

    <Required(ErrorMessage:="Price Required"), Range(1, 100, ErrorMessage:="Price must be between $1 and $100")>
    Public Property Price() As Decimal

    <StringLength(5)>
    Public Property Rating() As String
End Class

Answer 1

You can use ErrorMessageResourceType and ErrorMessageResourceName parameters to point to the resource file (.resx) with given string:

<Required(ErrorMessageResourceType:=GetType(Namespace.ResxFile),ErrorMessageResourceName:="GenreMustBeSpecified")>
Public Property Genre() As String

Then, You have to create one *.resx file for each language, like:

• ResxFile.resx – as default
• ResxFile.en-US.resx – english
• ResxFile.de-DE.res – german
• …