How to create dynamic expressions in nHibernate without using Criteria API.

[jhakasjk]

Hi,

I have below method

public IList<T> GetFiltered
(
int first, int maxresults,
Expression<Func<T, bool>> where,
Dictionary<Expression<Func<T, object>>, object> like,
Expression<Func<T, object>> orderBy, bool? asc,

out int count
)
{
ITransaction transaction = null;
try
{
ISession session = SessionProvider.Instance.CurrentSession;
using (transaction = session.BeginTransaction())
{
var query = session.QueryOver<T>();

// add where clause
if (where != null)
query = query.Where(where); //

// add like clause
if (like != null && like.Count > 0)
foreach (var likeItem in like)
query = query.WhereRestrictionOn(likeItem.Key).IsLike(like Item.Value);

// build count query set to run in the future
var query_count = query.Clone().ToRowCountQuery();
var future_count = query_count.FutureValue<int>();

// order by expression
if (orderBy != null)
{
if (!asc.HasValue)
asc = true;

query = asc.Value ? query.OrderBy(orderBy).Asc : query.OrderBy(orderBy).Desc;
}

// pagination
query.Skip(first);
query.Take(maxresults);

IList<T> entities = query.List();
count = future_count.Value;

transaction.Commit();

return entities;
}
}
catch (Exception)
{
if (transaction != null && transaction.IsActive)
transaction.Rollback();

throw;
}
}

at the time of calling this function, i want to send more than one where clause like this:- where => where.Project.ID == 167 && where.ID > 200 && where.Status == 0.

These where clause will decide at run-time based on some conditions like:

foreach (var expression in SearchExpArray)
{
switch (expression.Key)
{
case "Name":
Like.Add(like => like.Name, expression.Value + "%");
break;
case "Code":
Like.Add(like => like.Code, expression.Value + "%");
break;

}} // Example of like criteria.

I want the same like above for where clause too.

[Steve Bohlen]

You should post this question to the NHUSERS forum at http://groups.google.com/group/NHUSERS as its not SPRNET-related per se.