Question

再次使用我的应用程序的脚本界面。我想我现在有一个先进的dlr问题。

我有一个python脚本
我有一个.NET对象[o1]
我通过Iron Python从.NET调用python脚本上的方法。
python代码创建一个对象[o2]
python代码调用object [o1]上的方法，将[o2]作为参数传递（通过子类化DynamicMetaObject）
在o1方法的.NET代码中，我想在o2
例如我可以通过这样做
（（动态）o2）.FuncInPythonScript

所以我在.NET和Python之间有一个基本的双向控制流程。

我们走得更远：

在[o1]方法中，我在[o2]上使用LanguageContext.GetMemberNames
我想通过反思或表达方式以某种方式称呼这些成员。意思是我不想在步骤7中使用动态关键字。相反，不知何故通过反射调用方法。问题是： a）我不知道如何获取Python-Type的RuntimeType，这意味着我没有System.Reflection.MethodInfo所以我卡在这里 b）我尝试使用LanguageContext.CreateCallBinder和MetaObject.BindInvokeMember，所以我应该有方法'FuncInPythonScript'绑定但后来我陷入了如何最终调用绑定方法。

我看到我可以使用代码生成来生成代码，如步骤7所示，只需使用步骤8中的成员名称。但那真的有必要吗？

我没有看到更好的方法a）或b）可能有用，或者可能有一些我没想到的东西。

请不要回答基本的“如何从.NET调用python方法”提示。这是在步骤1-7中完成的，我这样做没有问题。这确实是一个先进的问题。

namespace DynamicMetaObjectTest
{
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    using System.IO;
    using System.Dynamic;
    using System.Linq.Expressions;
    using Microsoft.Scripting.Hosting;
    using Microsoft.Scripting.Hosting.Providers;

    class Program
    {
        internal sealed class CDotNetObject : IDynamicMetaObjectProvider
        {

            DynamicMetaObject IDynamicMetaObjectProvider.GetMetaObject(Expression aExp)
            {
                return new CInvoker(this, aExp);
            }

            private sealed class CInvoker : DynamicMetaObject
            {
                internal CInvoker(CDotNetObject aGws, Expression aExp) : base(aExp, BindingRestrictions.Empty, aGws)
                {
                    this.DotNetObject = aGws;
                }
                private readonly CDotNetObject DotNetObject;

                public override DynamicMetaObject BindGetMember(GetMemberBinder binder)
                {
                    var aMethodInfo = this.GetType().GetMethod("GetSetResultDelegate");
                    var aExp = Expression.Call(Expression.Constant(this), aMethodInfo);
                    var aRestrictions = BindingRestrictions.GetTypeRestriction(this.Expression, this.LimitType);                   
                    var aMetaObject = new DynamicMetaObject(aExp, aRestrictions);
                    return aMetaObject;                   
                }

                public Action<object> GetSetResultDelegate()
                {
                    return this.DotNetObject.SetResultProvider;
                }
            }
            public void SetResultProvider(object aPythonObject_O2)
            {
                var aResult = ((dynamic)aPythonObject_O2).GetResult(); // this is for noobs. ;-)

                var aMetaObjectProvider = (IDynamicMetaObjectProvider)aPythonObject_O2;
                var aMetaObject = aMetaObjectProvider.GetMetaObject(Expression.Constant(aPythonObject_O2));
                var aLanguageContext = HostingHelpers.GetLanguageContext(gScriptEngine);
                var aMemberNames = aLanguageContext.GetMemberNames(aPythonObject_O2);
                var aNonSystemMembers = from aMemberName in aMemberNames where !aMemberName.StartsWith("__") select aMemberName;

                foreach (var aMemberName in aNonSystemMembers)
                {
                    Console.WriteLine("Getting function result from Python script: " + aMemberName);


                    // Now problem:
                    // P1) How to determine wether its an function or an member variable?
                    // P2) How to invoke the method respectively get the value of the member variable?

                    // Your turn ;-)


                    // some of my failures:
                    { // does not work:
                        //var aVar1Binder = aLanguageContext.CreateGetMemberBinder("GetVar1", false);
                        //var aVar1Bound = aMetaObject.BindGetMember(aVar1Binder);
                        //var aCallInfo = new CallInfo(0 , new string[]{});
                        //var aInvokeBinder = aLanguageContext.CreateCallBinder("GetVar1", false, aCallInfo);
                        //var aInvokeBound = aMetaObject.BindInvokeMember(aInvokeBinder, new DynamicMetaObject[]{ aVar1Bound});
                        ////var aInvokeExp = Expression.Invoke(Expression.Constant(aInvokeBound), new Expression[] { });    
                    }
                    { // does not work
                        //var aExpandable = (IronPython.Runtime.Binding.IPythonExpandable)aMetaObject;
                    }
                }
            }           
        }

        static ScriptEngine gScriptEngine;

        static void Main(string[] args)
        {
            var aScriptRuntime = IronPython.Hosting.Python.CreateRuntime();         

            // That's the python script from step 1:
            var aCode = "class CustomView(object) :" + Environment.NewLine +
                        "\tdef GetResult(self) :" + Environment.NewLine +
                        "\t\treturn 42;" + Environment.NewLine +  // cuz 42 is the answer to everything ;-)
                        "DotNetObject.SetResultProvider(CustomView())";

            var aEngine = aScriptRuntime.GetEngine("py");
            gScriptEngine = aEngine;
            var aScope = aEngine.CreateScope();
            var aDotNetObject = new CDotNetObject();
            aScope.SetVariable("DotNetObject", aDotNetObject);

            // That's the invoke to pything from step 3:
            aEngine.Execute(aCode, aScope);
        }
    }
}

DLR：我真的需要代码生成吗？

（（动态）o2）.FuncInPythonScript

0 个答案: