如何在C＃中为linq设置值？

Question

I am very new with lambda expressions. I want to have the count of all the status_ID who has the number 6. Then I want to convert this as a list. What is the right syntax to set a value to the query? I know it in SQL but not in lambda expressions.

return ContextHelperSlowly<Moi>.GetCount(false, x => x.Status_ID == 6).ToList();

Kind regards

Update

  public static int GetCount(Func<T, bool> where, params Expression<Func<T, object>>[] navigationProperties)
    {
        int list;
        using (var context = GetContext())
        {
            IQueryable<T> dbQuery = context.Set<T>();
            if (null != navigationProperties)
            {
                foreach (Expression<Func<T, object>> navigationProperty in navigationProperties)
                {
                    dbQuery = dbQuery.Include(navigationProperty);
                }
            }
            if (null == where)
            {
                where = arg => true;
            }
            list = dbQuery
                .Where(x => x.Date_Deleted == null && x.End_Validity == null)
                .Where(where)
                .Count();
        }
        return list;
    }

Answer 1

I would just change your GetCount method to GetList:

public static List<T> GetList(Func<T, bool> where, params Expression<Func<T, object>>[] navigationProperties)
{
    using (var context = GetContext())
    {
        IQueryable<T> dbQuery = context.Set<T>();
        if (null != navigationProperties)
        {
            foreach (Expression<Func<T, object>> navigationProperty in navigationProperties)
            {
                dbQuery = dbQuery.Include(navigationProperty);
            }
        }
        if (null == where)
        {
            where = arg => true;
        }
        return dbQuery
            .Where(x => x.Date_Deleted == null 
                     && x.End_Validity == null
                     && where(x))
            .ToList();
    }
}

And use:

return ContextHelperSlowly<Moi>.GetList(false, x => x.Status_ID == 6);

To get the count as an int:

return ContextHelperSlowly<Moi>.GetList(false, x => x.Status_ID == 6).Count;

Answer 2

Why do you want to write those functions yourself?

this gives you the number of items with Status_ID = 6:

yourList.Count(x => x.Status_ID == 6);

and this gives you a list of all entries with Status_ID = 6:

yourList.Where(x => x.Status_ID == 6).ToList();

And a little notice for "code style". You can do this however you want, but C# standard would be "StatusId" for a property.