Please try any of the following:
EntityBase2 entity = (EntityBase2)containingEntity;
IPredicateExpression expression = new PredicateExpression();
EntityField2 timestampField =
(EntityField2) EntityFieldFactory.Create(entity.GetType().Name, "Stamp");
switch (predicateTypeToCreate)
{
case ConcurrencyPredicateType.Save:
expression.Add(timestampField == entity.Fields["Stamp"].DbValue);
break;
}
Or:
EntityBase2 entity = (EntityBase2)containingEntity;
IPredicateExpression expression = new PredicateExpression();
switch (predicateTypeToCreate)
{
case ConcurrencyPredicateType.Save:
expression.Add((EntityField2)entity.Fields["Version"] == entity.Fields["Version"].DbValue);
break;
}
ref: http://www.llblgen.com/TinyForum/Messages.aspx?ThreadID=15984