I have a class that looks something like this:
public class MyClass {
public string id { get; set; }
public string Id { get; set; }
public string SomethingMore {get; set;}
}
I don't control the class. So I have to live with the fact that both id (lowercase i) and Id (uppercase I) exist. Like it or not, I cannot change this, hence this answer answers my why, but it does not answer my how-to question.
In my Expression tree I have:
var newExpression = Expression.New(typeof(MyClass).GetConstructor(Type.EmptyTypes))
var propertyExpression = Expression.Property(newExpression, "Id");
The second line throws an Ambiguous Match Exception, because Expression.Property(..) is case insensitive - e.g. Expression.Property(newExpression, "SomethingMore") does not throw an exception.
What sort of work-around options do I have?
The next step in the code is:
Expression.Assign(propertyExpression, Expression.Constant("someNewValue", typeof(string));
I don't need to assign value to the id property and I know the meaning of id, which is special. I do however need to be able to assign a value to the Id property.
I guess I could create a derived version of my MyClass, that doesn't include the id property, but I need to do this at run-time. If this is the solution, how can it be done? Or, maybe there's a much better solution?
I don't control the MyClass. I only know that a developer would be inclined to define both idand Id in their class.
There are overloads for Expression.Property that allow a more explicit means of accessing the desired property.
Get the property info explicitly using reflection and use that.
var type = typeof(MyClass);
var newExpression = Expression.New(type.GetConstructor(Type.EmptyTypes));
PropertyInfo property = type.GetProperty("Id");
var propertyExpression = Expression.Property(newExpression, property);