c# - opérateur conditionnel dans Linq Expression provoque exception NHibernate - Stack Overflow

I'm trying to implement search functionality in an ASP.NET MVC 2 application. I create an expression based on criteria entered by the user:

public ViewResult FindCustomer( string forename, string familyname, DateTime? dob)
  {
  Expression<Func<Customer, bool>> searchCriteria = p => (
                                                            forename.IsNullOrEmpty() ? true : p.Forename == forename
                                                            && familyname.IsNullOrEmpty() ? true : p.FamilyNames.Any(n => n.Name == familyname)
                                                            && dob.HasValue ? true : p.DOB == dob
                                                            ); 

which then gets passed to a method in the repository

IQueryable<Customer> customers = CustomerRepository.FilterBy(searchCriteria);

The problem is when I run this I get the following exception

System.InvalidCastException: Unable to cast object of type 'NHibernate.Hql.Ast.HqlCast' to type 'NHibernate.Hql.Ast.HqlBooleanExpression'

According to this the problem is the use of the conditional operator in the expression.

So I suppose I have to create the Expression some other way but I'm not sure how to do that. I'm pretty new to Linq so any help would be gratefully accepted!

What about dynamically create your query? Like this:

var customers = CustomerRepository.AllEntities();

if (!forename.IsNullOrEmpty())
    customers = customers.Where(p => p.Forename == forename);
if (!familyname.IsNullOrEmpty())
    customers = customers.Where(p => p.FamilyNames.Any(n => n.Name==familyname));
if (dob.HasValue)
    customers = customers.Where(p => p.DOB == dob);

I don't know if this works but I think this could be more efficient.

I'm trying to implement search functionality in an ASP.NET MVC 2 application. I create an expression based on criteria entered by the user:

public ViewResult FindCustomer( string forename, string familyname, DateTime? dob)
  {
  Expression<Func<Customer, bool>> searchCriteria = p => (
                                                            forename.IsNullOrEmpty() ? true : p.Forename == forename
                                                            && familyname.IsNullOrEmpty() ? true : p.FamilyNames.Any(n => n.Name == familyname)
                                                            && dob.HasValue ? true : p.DOB == dob
                                                            ); 

which then gets passed to a method in the repository

IQueryable<Customer> customers = CustomerRepository.FilterBy(searchCriteria);

The problem is when I run this I get the following exception

System.InvalidCastException: Unable to cast object of type 'NHibernate.Hql.Ast.HqlCast' to type 'NHibernate.Hql.Ast.HqlBooleanExpression'

According to this the problem is the use of the conditional operator in the expression.

So I suppose I have to create the Expression some other way but I'm not sure how to do that. I'm pretty new to Linq so any help would be gratefully accepted!

What about dynamically create your query? Like this:

var customers = CustomerRepository.AllEntities();

if (!forename.IsNullOrEmpty())
    customers = customers.Where(p => p.Forename == forename);
if (!familyname.IsNullOrEmpty())
    customers = customers.Where(p => p.FamilyNames.Any(n => n.Name==familyname));
if (dob.HasValue)
    customers = customers.Where(p => p.DOB == dob);

I don't know if this works but I think this could be more efficient.

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