IronPython and Entity Framework

Question

Possibly really simple question, but I'm new to IronPython. I would like use IronPython to crawl an entity I pass to it, but when I try to use any extension methods, it, as sort of expected, blows up. How do I traverse my POCOs in IronPython?

delegate bool EvaluateRule(MyEntity entity);
//Keep in mind this is just to test, no actual value provided
string expression = @"entity.Flags.FirstOrDefault() == null";
MyEntity entity = new MyEntity();
PythonEngine engine = new PythonEngine();
EvaluateRule rule = engine.CreateLambda<EvaluateRule>(expression);
bool result = rule.Invoke(entity);

I get the following: 'EntityCollection[MyEntity]' object has no attribute 'FirstOrDefault'

Thanks in advance!

"it, as sort of expected, blows up"? What does this mean? 1) provide the smallest piece of code that shows the error. 2) provide the error. Our ESP isn't all that good. We can't guess what you've done or what "blows up" means. — S.Lott
– S.Lott, Commented Dec 2, 2010 at 18:54
Sorry, @S.Lott, was trying to be ambiguous as I was hoping for ideas without my implementation in mind. — Benny
– Benny, Commented Dec 2, 2010 at 19:14

Craig Stuntz · Accepted Answer · 2010-12-02 19:28:29Z

3

You can call the extension methods as regular static methods:

string expression = @"Enumerable.FirstOrDefault(entity.Flags) == null";

answered Dec 2, 2010 at 19:28

Craig Stuntz

127k12 gold badges257 silver badges275 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

Benny Over a year ago

If I do that, I get "name 'Enumerable' not defined"

Craig Stuntz Over a year ago

It's in System.Linq. You may need to reference that.

Benny Over a year ago

Sorry, I'm completely new to IronPython, how do I reference a namespace in my example above for IP to use?

Craig Stuntz Over a year ago

With import

Collectives™ on Stack Overflow

IronPython and Entity Framework

1 Answer 1

4 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

4 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related