Search IQuery Example

SearchIQuery.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using MedTest.Infrastructure.Entitys;
using NHibernate;
using NHibernate.Linq;
using MedTest.Infrastructure.NHibernate;

namespace MedTest.Core.Domain.Employees.Query
{
    public class GetEmployeeSearchQuery : IQuery<EmployeePagedList>
    {
        private readonly Guid _companyId;
        private string _searchTerm;
        private readonly int _skip;
        private readonly int _take;

        public GetEmployeeSearchQuery(Guid companyId, int skip, int take)
        {
            _companyId = companyId;
            _skip = skip;
            _take = take;
        }

        public GetEmployeeSearchQuery WithSearchTerm(string searchTerm)
        {
            _searchTerm = searchTerm;
            return this;
        }

        public EmployeePagedList Execute(ISession session)
        {
            var query = session.Query<Employee>()
                .Where(x => x.Company.Id == _companyId)
                .Where(GetFilters())
                .Skip((_skip - 1)*_take)
                .Take(_take)
                .Fetch(x => x.Company);

            var countQuery = session.Query<Employee>()
                .Where(x => x.Company.Id == _companyId)
                .Where(GetFilters());

            return new EmployeePagedList
                       {
                           Employees = query.ToList(),
                           Total = countQuery.Count()
                       };
        }

        private Expression<Func<Employee, bool>> GetFilters()
        {
            if (!string.IsNullOrEmpty(_searchTerm))
            {
                var terms = _searchTerm.Split(' ');
                Expression<Func<Employee, bool>> expression = x => x.Last.Contains(_searchTerm.Trim()) || x.First.Contains(_searchTerm.Trim()) || x.Number.Contains(_searchTerm.Trim());

                foreach(var term in terms)
                {
                    var s = term.Trim();
                    expression = expression.Or(x => x.Last.Contains(s) || x.First.Contains(s) || x.Number.Contains(s));
                }

                return expression;
            }
            return x => true;
        }
    }

    public class EmployeePagedList
    {
        public IEnumerable<Employee> Employees { get; set; }
        public int Total { get; set; }
    }
}