Revit API error on trying to invoke Microsoft.ML from an external command class, cant load system.memory error.

[frankholidayjunior]

So far what has worked is converting .netcore to .net frameworks 4.7.2 , calling from an external windows application using a windows form. As soon as i convert to a class use the external command I start getting these bizzarre errors. I have all the system.meory references in both projects an nuget seems to be effective at providing all the dependencies, however I keep getting the below "Cant load system.memory" error in one form or another exception.

************** Exception Text **************
System.FormatException: Parsing failed with an exception: The type initializer for 'System.MemoryExtensions' threw an exception. ---> System.TypeInitializationException: The type initializer for 'System.MemoryExtensions' threw an exception. ---> System.MissingMethodException: Method not found: 'IntPtr System.Runtime.CompilerServices.Unsafe.ByteOffset(!!0 ByRef, !!0 ByRef)'.
   at System.MemoryExtensions.MeasureStringAdjustment()
   at System.MemoryExtensions..cctor()
   --- End of inner exception stack trace ---
   at Microsoft.ML.Data.TextLoader.Parser.ParseRow(RowSet rows, Int32 irow, Helper helper, Boolean[] active, String path, Int64 line, String text)
   at Microsoft.ML.Data.TextLoader.Cursor.ParallelState.Parse(Int32 tid)
   at Microsoft.ML.Data.TextLoader.Cursor.ParallelState.ThreadProc(Object obj)
   --- End of inner exception stack trace ---
   at Microsoft.ML.Data.TextLoader.Cursor.<ParseParallel>d__33.MoveNext()
   at Microsoft.ML.Data.TextLoader.Cursor.MoveNextCore()
   at Microsoft.ML.Data.RootCursorBase.MoveNext()
   at Microsoft.ML.Transforms.ValueToKeyMappingTransformer.Train(IHostEnvironment env, IChannel ch, ColInfo[] infos, IDataView keyData, ColumnOptionsBase[] columns, IDataView trainingData, Boolean autoConvert)
   at Microsoft.ML.Transforms.ValueToKeyMappingTransformer..ctor(IHostEnvironment env, IDataView input, ColumnOptionsBase[] columns, IDataView keyData, Boolean autoConvert)
   at Microsoft.ML.Transforms.ValueToKeyMappingEstimator.Fit(IDataView input)
   at Microsoft.ML.Data.EstimatorChain`1.Fit(IDataView input)
   at Microsoft.ML.Data.EstimatorChain`1.Fit(IDataView input)
   at GitHubIssueClassification.DecisionTree.BuildAndTrainModel(IDataView trainingDataView, IEstimator`1 pipeline) in C:\Users\OCCIDENTALIS\Source\Repos\GitHubIssueClassification\DecisionTree.cs:line 56
   at GitHubIssueClassification.DecisionTree.TrainAndMakePredictions(String FamilyName, String Description) in C:\Users\OCCIDENTALIS\Source\Repos\GitHubIssueClassification\DecisionTree.cs:line 38
   at System.Windows.Forms.Control.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
   at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.ButtonBase.WndProc(Message& m)
   at System.Windows.Forms.Button.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

[mhannonQ65N2]

Do you have a reference to System.Runtime.CompilerServices.Unsafe and is it copied to your output directory (where your plugin dll is)? Also, all your references are for .net framework, right?

[frankholidayjunior]

Hi M Hannon,

I checked the System.Runtime.CompilerServices.Unsafe is being output to the same directory as my external command .dll

AFAIK all my references were to .netframeworks 4.7.2, microsoft.ml didnt have any incomaptability issues either i could compile in that framework. I did get around this problem by reading the console output. And i sent arguments to the console aswell. 

[bvgarbar]

Hi!

I Have the same problem...
Can you explain please, how to resolve it?

Best Regards,
Bogdan.