Question

o will always come from an entiryRef/TEntity (from linq 2 sql)

I’m ok with a c# or vb.net solution (I will convert it into vb.net if you can’t)

Public Function desc(Of t)(ByRef o As t, Optional ByVal PropPrefix As String = "desc") As String
    If o Is Nothing Then
        Return ""
    Else
        Dim bind = Reflection.BindingFlags.Public Or Reflection.BindingFlags.IgnoreCase Or Reflection.BindingFlags.Instance
        Dim _desc = PropPrefix & If(var.Sess.lang = Sess.elang.en, PropPrefix & "en", "fr")
        Dim pinfo As Reflection.PropertyInfo = o.GetType.GetProperty(_desc, bind)

        Return pinfo.GetValue(o, Nothing).ToString
    End If
End Function

little background

I have a database like this

tableUser
-----------------
id
name
countryid

tableCountry
--------
countryid
descEn
descFr

when I’m showing the information about a user, I want to easily show the good language selected in the application

that one example, I have lots more table and lot more lookup table

with linq 2 sql if the field in the database is null, the object will be “nothing”(null) and I’m catching that with the first if then I’m getting the corresponding language field

Answer 1

Unfortunately, runtime reflection will be required unless you can integrate a desc method into each object, perhaps through some sort of entity base class or code generation and partial classes.

The code generation approach: For each entity class, if it contains one or more descFoo properties, generate a desc property that pulls the correct one. If you cannot modify the CodeDom before it is written, you can also compile the entity classes, reflect/introspect the results, generate partial classes, and recompile with the added code.

Since these are entity classes, though, it appears to me as though a schema change might be preferable. Rather than using multiple descFoo columns, add a table consisting of {entity PK, language, text}.