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将对象实例传递给Roslyn ScriptEngine

roslyn .net c#

MarkSh · 技术社区 · 11 年前

我正在寻找一个C#脚本引擎,它可以解释C#代码块,同时维护上下文。例如,如果输入: var a = 1; ,然后 a + 3 ,它将输出 4 . 我知道MS Roslyn ,它确实做到了这一点,但这是一个沙盒(相对于启动它的程序)。因此,如果我创建 ScriptEngine 以及 MyClass (只是我的一个业余班),我没有办法通过 my_class 到 script_engine .

有没有可能 传递该引用 ?

什么我想要做的是:

ScriptEngine engine; // A Roslyn object
Session session // A Roslyn object

MyClass my_class; // My object

// all required initializations

Submission<object> sm = session.CompileSubmission<object>("var a=1;"); 
dynamic result = sm.Execute(); 

Submission<object> sm = session.CompileSubmission<object>("a + 3;"); 
dynamic result = sm.Execute(); // result is now 4

MyClass my_class;
session.AddReferenceToAnOject(my_class); // function that does not exists, but reflect my intention

Submission<object> sm = session.CompileSubmission<object>("my_class.ToString();"); 
dynamic result = sm.Execute();  // result is no the output of my_class.ToString()

请注意 AddReferenceToAnOject() 是缺失的部分,因为罗斯林中没有这样的功能。

2 回复 | 直到 11 年前

andyp 11 年前

答案在 link @Herman评论道。

事实证明,罗斯琳 ScriptEngine/Session 支持以下概念 Host Object . 为了使用它,请定义所选的类,并在创建会话时传递它。这样做,一切 平民的 该主机对象的成员,可用于会话内的上下文:

public class MyHostObject
{
    public List<int> list_of_ints;
    public int an_int = 23;
}

var hostObject = new MyHostObject();
hostObject.list_of_ints = new List<int>();
hostObject.list_of_ints.Add(2);
var engine = new ScriptEngine(new[] { hostObject.GetType().Assembly.Location });

// passing reference to hostObject upon session creation
var session = Session.Create(hostObject);

// prints `24` to console
engine.Execute(@"System.Console.WriteLine(an_int + list_of_ints.Count);", 
               session);

Tone Å koda 11 年前

下面是如何将变量从对象传递到roslyn动态执行代码的完整过程。还包括eval()包装器。首先从microsoft.com安装RoslynSetup.exe http://www.microsoft.com/en-sa/download/details.aspx?id=34685

然后将引用Roslyn.Compilers和Roslyn.Ccompilers.CSharp添加到项目(程序集/扩展)

以下是vs2012中C#控制台应用程序的完整工作代码。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Roslyn.Compilers;
using Roslyn.Compilers.CSharp;
using Roslyn.Scripting;
using Roslyn.Scripting.CSharp;

namespace testRoslyn
{
    class Program
    {
        static void Main(string[] args)
        {
            TestRoslyn tr = new TestRoslyn();
            tr.Test = "this was set from main program ";
            tr.test();
            System.Console.WriteLine(tr.Test);
            tr.Test = "this was set from main program for eval";
            Eval e = new Eval();
            e.create<TestRoslyn>(tr);                           
            e.eval("Test = Test + \" AND THIS WAS SET FROM Eval()\";");
            System.Console.WriteLine(tr.Test);
            string a = e.eval<string>("string a = \"return this from eval\";a");
            System.Console.WriteLine(a);
            tr.Test = "now return this";
            string b = e.eval<string>("string a = Test + \" ... and this\";a");
            System.Console.WriteLine(b);
            double d = e.eval<double>("double dbl = 1.2345*3;dbl");
            System.Console.WriteLine(d);
            e.eval("string testIt(string a){return \"testIt(): \"+a+\"\";}");
            string c = e.eval<string>("string c = testIt(\"nice\");c");
            System.Console.WriteLine(c);
            Console.ReadKey();
        }
    }

    public class TestRoslyn
    {
        public string Test;

        public TestRoslyn()
        {
        }

        public string test()
        {
            ScriptEngine roslynEngine = new ScriptEngine();
            Roslyn.Scripting.Session session = roslynEngine.CreateSession(this);
            session.AddReference(this.GetType().Assembly);
            session.AddReference("System.Web");
            session.ImportNamespace("System");
            session.ImportNamespace("System.Web");
            var result = (string)session.Execute("Test = Test + \" ... and this was set from roslyn code.\";Test");
            return result;
        }
    }

    public class Eval
    {
        ScriptEngine RoslynEngine = new ScriptEngine();
        Roslyn.Scripting.Session Session;

        public void create<T>(T hostObject = null) where T : class
        {
            RoslynEngine = new ScriptEngine();
            Session = RoslynEngine.CreateSession(hostObject);
            if (hostObject != null)
                Session.AddReference(hostObject.GetType().Assembly);
            Session.AddReference("System.Web");
            Session.ImportNamespace("System");
            Session.ImportNamespace("System.Web");
        }

        public void eval (string strEval)
        {                                                
            Session.Execute(strEval);
        }

        public T eval<T>(string strEval) 
        {
            return (T) Session.Execute(strEval);            
        }
    }
}