public DemoQueryableImp(IDemoQueryProvider queryProvider, Expression expression)
{
_queryProvider = queryProvider ?? throw new ArgumentException("can not be null", nameof(queryProvider));
_expression = expression ?? throw new ArgumentException("can not be null", nameof(expression));
}
public DemoQueryableImp(IDemoQueryProvider queryProvider)
{
_queryProvider = queryProvider;
_expression = Expression.Constant(this, typeof(IDemoQueryable <T>));
}
