René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"RuntimeBinderException - Cannot implicitly convert type 'Python.Runtime.PyObject' to 'System.Collections.Generic.List\u003cstring\u003e'","articleBody":"## Environment\r\n\r\n-   Pythonnet version: 2.3.0\r\n-   Python version: 3.6 (Anaconda 32-bit)\r\n-   Operating System: Windows 10\r\n\r\n## Details\r\n\r\nI have the following code:\r\n\r\n### Interface1.cs\r\n\r\n```csharp\r\nusing System.Collections.Generic;\r\n\r\npublic interface Interface1\r\n{\r\n    string Test();\r\n\r\n    List\u003cstring\u003e GetList();\r\n\r\n    List\u003cMyType\u003e GetListOfMyType();\r\n}\r\n\r\npublic class MyType\r\n{\r\n}\r\n```\r\n\r\n### Class1.cs\r\n\r\n```csharp\r\nusing System.Collections.Generic;\r\n\r\nnamespace Python.EmbeddingTest\r\n{\r\n    public class Class1 : Interface1\r\n    {\r\n        public string Test()\r\n        {\r\n            return \"test\";\r\n        }\r\n\r\n        public List\u003cstring\u003e GetList()\r\n        {\r\n            return new List\u003cstring\u003e() { \"testing\" };\r\n        }\r\n\r\n        public List\u003cMyType\u003e GetListOfMyType()\r\n        {\r\n            return new List\u003cMyType\u003e() { new MyType(), new MyType() };\r\n        }\r\n    }\r\n}\r\n```\r\n\r\n### Module1.py\r\n\r\n```python\r\nimport clr\r\n\r\nclr.AddReference(\"Python.EmbeddingTest\")\r\nfrom Python.EmbeddingTest import *\r\n\r\nclass Class2(Class1):\r\n\r\n    def Test(self):\r\n        return \"Test from Class2\"\r\n    \r\n    def Method1(self):\r\n        return \"Method1\"\r\n```\r\n\r\n### Test\r\n\r\nI am trying to do something like what the following test is trying to do:\r\n\r\n```csharp\r\n[Test]\r\npublic void TestGenericListMarshalling()\r\n{\r\n    var scope = Py.Import(\"module1\");\r\n    var attr = scope.GetAttr(\"Class2\");\r\n    dynamic c2 = attr.Invoke();\r\n    List\u003cstring\u003e ls = c2.GetList();\r\n}\r\n```\r\n\r\n### Exception\r\n\r\nHowever, I get the following exception:\r\n\r\n```\r\nMicrosoft.CSharp.RuntimeBinder.RuntimeBinderException occurred\r\n  HResult=0x80131500\r\n  Message=Cannot implicitly convert type 'Python.Runtime.PyObject' to 'System.Collections.Generic.List\u003cstring\u003e'\r\n  Source=Python.EmbeddingTest\r\n  StackTrace:\r\n   at Python.EmbeddingTest.PyImportTest.TestGenericListMarshalling() in D:\\Users\\Tom\\Dropbox\\Algo Trading\\pythonnet\\src\\embed_tests\\pyimport.cs:line 90\r\n```\r\n\r\nIs it possible to marshall generic .NET Lists?","author":{"url":"https://github.com/tomhunter-gh","@type":"Person","name":"tomhunter-gh"},"datePublished":"2017-04-05T20:10:53.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":10},"url":"https://github.com/451/pythonnet/issues/451"}