public IEnumerable <ValidationMessage> Requires(AccountCommand command)
{
if (string.IsNullOrWhiteSpace(command.AccountId))
{
yield return(ValidationMessage.Error("Account id cannot be empty", nameof(command.AccountId)));
}
}
public IEnumerable <ValidationMessage> Requires(AccountCommand command, AccountState before)
{
if (command.AccountId != before.AccountId)
{
yield return(ValidationMessage.Error("This is not the right account", nameof(command.AccountId), nameof(before.AccountId)));
}
}