Question

In C#, imagine I have the following object:

var myObject = new
{
    Val = new[]
    {
        new { ArrVal = "three1"},
        new { ArrVal = "three2"}
    }
};

How would I dynamically evaluate the following expression against the object? (the expression is a string)

"Val[1].ArrVal"

In this case I would expect the expression to return “three2”. I’d like to write a method with the following signature:

object GetValue(string expression, object objectToExtractValueFrom)

Can I do this with reflection, or somehow with the dynamic keyword?

Answer 1

You can’t do it either with reflection or with dynamic keyword. What you can do is:

1. parse the string in order to create an lambda expression tree that
   will be compiled and executed against your parameter(s)
2. use CodeDOM
3. use some dynamic language like IronRuby or IronPython