CustomValidationAttribute doesn't work when other attributes are applied to the class.

i reported on microsoft connect, closed won't fix, if have workarounds (other searching attributes manually), please let me know.

here problem:

imports system.componentmodel  imports system.componentmodel.dataannotations  module module1     sub main()    dim type = gettype(contact)    typedescriptor.addprovidertransparent(     new associatedmetadatatypetypedescriptionprovider(type), type)        dim contact new contact    dim context new validationcontext(contact, nothing, nothing)    dim errors new list(of validationresult)    dim result = validator.tryvalidateobject(contact, context, errors, true)   end sub  end module    <customvalidation(gettype(contact.contactmd), "*********************")>  <metadatatype(gettype(contact.contactmd))>  public class contact     public property email string   public property emailrepeat string     public class contactmd      '<required()>    public property email    '<required()>    public property emailrepeat      public shared function validateemails(byval contact contact) _      validationresult     return if(contact.email = contact.emailrepeat,          validationresult.success,          new validationresult("fail!"))    end function   end class  end class

the above code throw exception: 
customvalidationattribute method '*********************' not exist in type 'contactmd' or not public , static.

this exception justified , it's sign things working.
once uncomment requiredattribute attributes on properties in metadata class, exception not thrown, means, validation system doesn't validate both property-typed attributes , class-level attributes.

any workarou

internally validation happens in several (currently 3) steps. if there errors found in 1 of steps, next steps not executed , errors returned immediatelly. looks design.

in case first step fails validate email , emailrepeat properties, because nothing - if pass 3rd argument (icollection<validationresult>), you will information. next steps of validation include class-level attributes not executed because of these validation errors first step. that's why not see exception.

-karel

.NET Framework  >  Common Language Runtime Internals and Architecture