[Solved]-Creating Dynamic Search Queries with Entity Framework Web API using passed in parameters as the search fields-LINQ,C#

You can use ObjectQuery class and Sql operators to build your Dynamic query, something like this

public List<EMPLOYEE> Get([FromUri] EMPLOYEE query)
        {

            List<EMPLOYEE> emps = new List<EMPLOYEE>();
            var db = AuthHandler.Ent;
            var queryable = (ObjectQuery<EMPLOYEE>)db.EMPLOYEES.AsExpandable();

            string condition = "CONTAINS(@column, @search)";

            foreach (var prop in query.GetType().GetProperties())
            {
                var value = prop.GetValue(query, null);
                if (value != null)
                {
                    queryable = queryable.Where(string.Format(condition, prop.Name, value));
                }
            }
            emps = queryable.ToList();

            return emps;

        }

am i right?

I will use a predicate builder like this

public static class PredicateBuilder
{
    public static Expression<Func<T, bool>> True<T>() { return f => true; }
    public static Expression<Func<T, bool>> False<T>() { return f => false; }

    public static Expression<Func<T, bool>> Or<T>(this Expression<Func<T, bool>> expr1,
                                                        Expression<Func<T, bool>> expr2)
    {
        var invokedExpr = Expression.Invoke(expr2, expr1.Parameters.Cast<Expression>());
        return Expression.Lambda<Func<T, bool>>
              (Expression.OrElse(expr1.Body, invokedExpr), expr1.Parameters);
    }

    public static Expression<Func<T, bool>> And<T>(this Expression<Func<T, bool>> expr1,
                                                         Expression<Func<T, bool>> expr2)
    {
        var invokedExpr = Expression.Invoke(expr2, expr1.Parameters.Cast<Expression>());
        return Expression.Lambda<Func<T, bool>>
              (Expression.AndAlso(expr1.Body, invokedExpr), expr1.Parameters);
    }
}

And use it like this :

public IQueryable<Customer> GetCustomers(CustomerOrderSearchParameters parameters)
        {    
                context.Database.Log = s => System.Diagnostics.Debug.WriteLine(s);
                var predicate = PredicateBuilder.True<Customer>();
                if (!string.IsNullOrEmpty(parameters.FirstName))
                {
                    predicate = predicate.And(x => x.FirstName.Contains(parameters.FirstName));
                }
                if (!string.IsNullOrEmpty(parameters.LastName))
                {
                    predicate = predicate.And(x => x.LastName.Contains(parameters.LastName));
                }
                if (!string.IsNullOrEmpty(parameters.Email))
                {
                    predicate = predicate.And(x => x.email.Contains(parameters.Email));
                }
                if (!string.IsNullOrEmpty(parameters.PhoneNumber))
                {
                    predicate = predicate.And(x => x.MobilePhone.Contains(parameters.PhoneNumber) || x.HomePhone.Contains(parameters.PhoneNumber));
                }
                if (parameters.BrandID != null)
                {
                    predicate = predicate.And(x => x.Logins.Where(l => l.BrandID == parameters.BrandID).Any());
                }
                if (parameters.ShowNoOrders == true)
                {
                    predicate = predicate.And(x => x.Orders.Where(o => o.CustomerID != x.CustomerID).Any());
                }                
                return context.Customers.AsExpandable().Where(predicate);           
        }

Also the CustomerOrderSearchParameters is just a list of simple parameters (equivalent of what you will get from your query)