How to get the value of a lambda expression

Say we have the following :

        private static string Query<T>(Expression<Func<T, bool>> pr)
        {
            return pr.ToString();
        }
...
int ii = 1000;
string str = Query((SalesInvoiceRow r) => r.Serial > ii && r.CustomerName.Contains( "23"));

When you run the above we get:

r => ((r.Serial > value(testing.program+<>c__DisplayClass0).ii) AndAlso r.CustomerName.Contains("23"))

How can we get the value of ii instead of the ugly statement like below?

r => ((r.Serial > 1000) AndAlso r.CustomerName.Contains("23"))

Tags: C#