Access property in lambda expression from string when using LINQ

Question

How can I do something like this:

var result = db.MyTable.Where(x => x.\"MyProperty\" == \"Test\" );

As you can see I want to access \"MyProperty\" but

Answer 1

You can use reflection to get it unless you are querying a database directly using LINQ to SQL.

Here is a sample of how to get property info using reflection:

class Program
{
    class Person
    {
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public byte Age { get; set; }
        public override string ToString()
        {
            return string.Format("{0}, {1} ({2})", LastName, FirstName, Age);
        }
    }

    static void Main(string[] args)
    {
        Person p1 = new Person() { FirstName = "Bill", LastName = "Johnson", Age = 34 };
        Person p2 = new Person() { FirstName = "Sally", LastName = "Jones", Age = 21 };
        Person p3 = new Person() { FirstName = "Jame", LastName = "Smith", Age = 28 };

        List people = new List(new Person[] { p1, p2, p3 });

        IEnumerable foundPeople = people.Where(p => p.GetType().GetProperty("LastName").GetValue(p,null).ToString().StartsWith("J"));

        foreach (Person person in foundPeople)
        {
            Console.WriteLine(person.ToString());
        }
        Console.ReadKey();
    }
}

Just be careful because this could lead to performance issues if you are querying a large amount data.