c# - Linq Dynamic OR condition -

i having user table this,

id(int) name(string), state_id(int64), country_id(int64), mobilenumber(string), email(string), identity(string) role_id disable(boolean) 

identity column have values comma separated example(,mole in hand, mole in face,). value pre-defined,

now have request this,

class userrequest { public string rolename{get;set;} public string countryname{get;set;} publi string statename{get;set;} publi ilist<string> identitylst{get;set;} } 

using request want form query.

public ilist<user> getuser(userrequest req) {   iqueryable<user> query=datacontext.user.where(a=>!a.isdisable)  if(string.isnullorempty(req.rolename))  {   query=from qu in query       role in datacontext.role.where(a=>a.id==qu.role.id)       role.name==req.rolename       select qu; }  if(string.isnullorempty(req.countryname)) { query=from qu in query       country in datacontext.country.where(a=>a.id==qu.country.id)       country.name==req.countryname       select qu; }  if(string.isnullorempty(req.statename)) { query=from qu in query       state in datacontext.state.where(a=>a.id==qu.state.id)       state.name==req.statename       select qu; }  if(req.identitylst!=null) { /////here need query or condition, possible.  /////for example if identity list have 3 value. need 3 or condition  } } 

please me out of problem, if identitylst have 10 value hitting db 10 times.

don't qry on server post filtering @ runtime.

public ilist<user> getuser(userrequest req){     //remove [if(req.identitylst!=null)] part }  public bool containsidentity(ilist<string> x, ilist<string> y) {     if( x == null || y == null ) return false;     return x.any(test => y.contains(test)); }  var users = getuser(req).tolist(); var filtered = users.where( u => containsidentity(u.identity.split(','), req.identitylst ));