從IronPython調用C＃方法

Question

我正在構建一個C＃WebKit Web瀏覽器，該瀏覽器可以通過IronPython實現自動化以幫助進行質量保證測試。我將使用IronPython創建測試計劃，該計劃將運行許多瀏覽器方法，提供參數並評估結果。

IronPython的大部分文檔說明了如何使用C＃調用IronPython方法，但我已經想出瞭如何爲方法設置參數，以及如何檢索方法返回值，但不是來自同一方法。在下面的例子中你會注意到，我將一個參數傳遞給一個方法，該方法依次設置一個類成員變量，然後用另一種方法檢索該值。

任何人都可以提出一個更優雅的模式？

using System; 
using System.Windows.Forms; 
using IronPython.Hosting; 
using Microsoft.Scripting; 
using Microsoft.Scripting.Hosting; 

namespace PythonScripting.TestApp 
{ 

public partial class Form1 : Form 
{ 
    private ScriptEngine m_engine = Python.CreateEngine(); 
    private ScriptScope m_scope = null; 

    //used to call funcs by Python that dont need to return vals 
    delegate void VoidFunc(string val); 

    public Form1() 
    { 
     InitializeComponent(); 
    } 

    private void doSomething() 
    { 
     MessageBox.Show("Something Done", "TestApp Result"); 
    } 

    private string _rslt = ""; 

    private string getSomething() 
    { 
     return _rslt; 
    } 

    private void setSomething(string val) 
    { 
     _rslt = val; 
    } 

    private void Form1_Load(object sender, EventArgs e) 
    { 
     m_scope = m_engine.CreateScope(); 

     Func<string> PyGetFunction = new Func<string>(getSomething); 
     VoidFunc PySetFunction = new VoidFunc(setSomething); 

     m_scope.SetVariable("txt", txtBoxTarget); 
     m_scope.SetVariable("get_something", PyGetFunction); 
     m_scope.SetVariable("set_something", PySetFunction);   
    } 

    private void button1_Click(object sender, EventArgs e) 
    { 
     string code = comboBox1.Text.Trim(); 
     ScriptSource source = m_engine.CreateScriptSourceFromString(code, SourceCodeKind.SingleStatement); 

     try 
     { 
      source.Execute(m_scope); 
      Func<string> result = m_scope.GetVariable<Func<string>>("get_something"); 

      MessageBox.Show("Result: " + result(), "TestApp Result"); 
     } 
     catch (Exception ue) 
     { 
      MessageBox.Show("Unrecognized Python Error\n\n" + ue.GetBaseException(), "Python Script Error"); 
     } 
    } 
} 
} 

Answer 1

在正常情況下，IronPython的只能訪問公共類和成員的.NET類型。您應該能夠將範圍內的對象設置爲變量，並從腳本訪問該對象上的任何公共成員。然而，你在你的例子中的方法是private因此，你不能真正訪問它們。如果您希望能夠訪問它們，您需要以某種方式公開非公開成員，以便您可以操縱它們或使用反射。

您可以嘗試的模式是添加一個方法，該方法將爲您的對象創建一個代理，該代理將擁有您想要公開的所有方法。然後將該代理對象添加到您的作用域，然後使用該代理來調用您的方法。

public partial class MyForm : Form 
{ 
    private readonly ScriptEngine m_engine; 
    private readonly ScriptScope m_scope; 

    public MyForm() 
    { 
     InitializeComponent(); 
     m_engine = Python.CreateEngine(); 

     dynamic scope = m_scope = m_engine.CreateScope(); 
     // add this form to the scope 
     scope.form = this; 
     // add the proxy to the scope 
     scope.proxy = CreateProxy(); 
    } 

    // public so accessible from a IronPython script 
    public void ShowMessage(string message) 
    { 
     MessageBox.Show(message); 
    } 

    // private so not accessible from a IronPython script 
    private int MyPrivateFunction() 
    { 
     MessageBox.Show("Called MyForm.MyPrivateFunction"); 
     return 42; 
    } 

    private object CreateProxy() 
    { 
     // let's expose all methods we want to access from a script 
     dynamic proxy = new ExpandoObject(); 
     proxy.ShowMessage = new Action<string>(ShowMessage); 
     proxy.MyPrivateFunction = new Func<int>(MyPrivateFunction); 
     return proxy; 
    } 
} 

有了這個，你可以執行腳本通過form變量或通過proxy變量代理訪問你的形式。爲了更好的衡量，您可以輕鬆訪問示波器中的變量和其他對象。

private void DoTests() 
{ 
    // try to call the methods on the form or proxy objects 
    var script = @" 
form.ShowMessage('called form.ShowMessage') 
# formFuncResult = form.MyPrivateFunction() # fail, MyPrivateFunction is not accessible 
proxy.ShowMessage('called proxy.ShowMessage') 
proxyFuncResult = proxy.MyPrivateFunction() # success, MyPrivateFunction on the proxy is accessible 
"; 
    m_engine.Execute(script, m_scope); 

    // access the scope through a dynamic variable 
    dynamic scope = m_scope; 

    // get the proxyFuncResult variable 
    int proxyFuncResult = scope.proxyFuncResult; 
    MessageBox.Show("proxyFuncResult variable: " + proxyFuncResult); 

    // call the the function on the proxy directly 
    int directResult = scope.proxy.MyPrivateFunction(); 
    MessageBox.Show("result of MyPrivateFunction: " + directResult); 
} 

Answer 2

我不確定你想達到什麼樣的，但是怎麼樣？

在C＃：

m_scope.SetVariable("myAssembly", System.Reflection.Assembly.GetExecutingAssembly()); 

[...] 

var result = (string) m_scope.GetVariable("theOutVar"); 

然後在IronPython的腳本：

import clr 
clr.AddReference(myAssembly) 
import MyNamespace 
theOutVar = MyNamespace.MyClass.MyStaticMethod("hi") 

或許這樣嗎？

在C＃：

m_scope.SetVariable("theTestObject", myTestObj); 

而且在IronPython的：

result = myTestObj.DoSomething("hi there", 10, false)