我如何將匿名操作綁定爲使用反射的新事件處理程序

Question

我正在爲Windows窗體編寫大量單元測試，並且至今已經能夠弄清楚如何設置私有控件的屬性並調用其方法，反射。但我堅持如何將內聯lambda關聯到其中一個控件上發生的事件，在這種情況下是DataGridView的DataSourceChanged事件。

public static void ObserveGrid(this Form form, string controlName, Action action) 
{ 
    var controls = form.Controls.Find(controlName, true); 
    if (controls.Any()) 
    { 
     var control = controls[0] as DataGridView; 
     if (control != null) 
     { 
      EventInfo ei = typeof(DataGridView).GetEvent("DataSourceChanged"); 
      if (ei != null) 
      { 
       ei.AddEventHandler(control, Delegate.CreateDelegate(ei.EventHandlerType, control, action.Method)); 
      } 
     } 
    } 
} 

我希望能這樣稱呼它：

var monitor = new Mutex(); 
form.ObserveGrid("dataGridView1", 
    () => 
    { 
     Trace.WriteLine("Releasing mutex."); 
     monitor.ReleaseMutex(); 
    }); 
var sw = new Stopwatch(); 
form.ClickButton("btnSearch", sw); 
monitor.WaitOne(); 
sw.Stop(); 

在執行過程中，我得到了一個錯誤：

Cannot bind to the target method because its signature or security transparency is not compatible with that of the delegate type.

我是什麼在這種情況下做錯了什麼？

UPDATE：

使用this偉大的職位，我已經改變了我的擴展類，像這樣：

public static void ObserveGrid(this Form form, string controlName, Action<object,object> action) 
    { 
     var controls = form.Controls.Find(controlName, true); 
     if (controls.Any()) 
     { 
      var control = controls[0] as DataGridView; 
      if (control != null) 
      { 
       EventInfo ei = typeof(DataGridView).GetEvent("DataSourceChanged"); 
       if (ei != null) 
       { 
        Delegate handler = ConvertDelegate(action, ei.EventHandlerType); 
        ei.AddEventHandler(control, handler); 
       } 
      } 
     } 
    } 

    public static Delegate ConvertDelegate(Delegate originalDelegate, Type targetDelegateType) 
    { 
     return Delegate.CreateDelegate(
      targetDelegateType, 
      originalDelegate.Target, 
      originalDelegate.Method); 
    } 

但是我得到的另一個錯誤，這一次有關從非同步釋放互斥螺紋：

Releasing mutex. System.Reflection.TargetInvocationException : Exception has been thrown by the target of an invocation. ----> System.ApplicationException : Object synchronization method was called from an unsynchronized block of code.

更新2

爲SemaphoreSlim交換互斥鎖解決了同步問題。

Answer 1

這裏是我落得這樣做：

首先，擴展類：現在

public static class Extensions 
{ 
    #region Public Methods and Operators 

    public static Stopwatch ClickButton(this Form form, string controlName) 
    { 
     var controls = form.Controls.Find(controlName, true); 
     if (controls.Any()) 
     { 
      var control = controls[0] as Button; 
      if (control != null) 
      { 
       MethodInfo mi = typeof(Button).GetMethod("OnClick", BindingFlags.NonPublic | BindingFlags.Instance); 
       var stopWatch = Stopwatch.StartNew(); 
       mi.Invoke(
        control, 
        new object[] 
        { 
         EventArgs.Empty 
        }); 
       return stopWatch; 
      } 
     } 
     throw new ApplicationException("Control not found or of invalid Type"); 
    } 

    public static Delegate ConvertDelegate(Delegate originalDelegate, Type targetDelegateType) 
    { 
     return Delegate.CreateDelegate(targetDelegateType, originalDelegate.Target, originalDelegate.Method); 
    } 

    public static object GetControlProperty<T>(this Form form, string controlName, string propertyName) where T : class 
    { 
     var controls = form.Controls.Find(controlName, true); 
     if (controls.Any()) 
     { 
      var control = controls[0]; 
      PropertyInfo pi = typeof(T).GetProperty(propertyName); 
      return pi.GetValue(control, null); 
     } 
     throw new ApplicationException("Control not found or of invalid Type"); 
    } 

    public static void ObserveControlEvents<T>(this Form form, string controlName, string eventName, Action<object, object> action) where T : class 
    { 
     var controls = form.Controls.Find(controlName, true); 
     if (controls.Any()) 
     { 
      var control = controls[0] as T; 
      if (control != null) 
      { 
       EventInfo ei = typeof(T).GetEvent(eventName); 
       if (ei != null) 
       { 
        Delegate handler = ConvertDelegate(action, ei.EventHandlerType); 
        ei.AddEventHandler(control, handler); 
       } 
      } 
     } 
    } 

    public static void ObserveGrid(this Form form, string controlName, string eventName, Action<object, object> action) 
    { 
     var controls = form.Controls.Find(controlName, true); 
     if (controls.Any()) 
     { 
      var control = controls[0] as DataGridView; 
      if (control != null) 
      { 
       EventInfo ei = typeof(DataGridView).GetEvent(eventName); 
       if (ei != null) 
       { 
        Delegate handler = ConvertDelegate(action, ei.EventHandlerType); 
        ei.AddEventHandler(control, handler); 
       } 
      } 
     } 
    } 

    public static void SetControlProperty<T>(this Form form, string controlName, string propertyName, object value) where T : class 
    { 
     var controls = form.Controls.Find(controlName, true); 
     if (controls.Any()) 
     { 
      var control = controls[0]; 
      PropertyInfo pi = typeof(T).GetProperty(propertyName); 
      pi.SetValue(control, value, null); 
     } 
    } 

    public static void SetFormProperty(this Form form, string controlName, object value) 
    { 
     var controls = form.Controls.Find(controlName, true); 
     if (controls.Any()) 
     { 
      var control = controls[0]; 
      PropertyInfo pi = typeof(Control).GetProperty("Text"); 
      pi.SetValue(control, value, null); 
     } 
    } 

    #endregion 
} 

，在我的單元測試，我可以創建表格，設定值，觸發和觀察的事件：

[TestFixture] 
public class FormsTests 
{ 
    #region Public Methods and Operators 

    [TestCase(null, null, null, 1000)] 
    [TestCase("Kim", null, null, 500)] 
    [TestCase("Kim", null, "Akers", 250)] 
    [TestCase("Kim", "B", "Abercrombie", 100)] 
    public void InsuredSearcherResponseTimeWithReflectionTest(string firstName, string middleName, string lastName, long milliseconds) 
    { 
     var monitor = new SemaphoreSlim(1); 
     monitor.Wait(); 
     var form = new Insured(); 
     form.SetControlProperty<TextBox>("tbFirstName", "Text", firstName); 
     form.SetControlProperty<TextBox>("tbMiddleName", "Text", middleName); 
     form.SetControlProperty<TextBox>("tbLastName", "Text", lastName); 
     form.ObserveControlEvents<DataGridView>(
      "dataGridView1", 
      "DataSourceChanged", 
      (sender, args) => 
      { 
       Trace.WriteLine("Occured in delegate"); 
       monitor.Release(); 
      }); 
     Trace.WriteLine("Executing"); 
     var sw = form.ClickButton("btnSearch"); 
     monitor.Wait(); 
     sw.Stop(); 
     Trace.WriteLine(String.Format("Row count was {0} took {1}ms to process", form.GetControlProperty<DataGridView>("dataGridView1", "RowCount"), sw.ElapsedMilliseconds)); 
     Assert.IsTrue(sw.ElapsedMilliseconds < milliseconds); 
    } 

    [TestFixtureSetUp] 
    public void TestFixtureSetup() 
    { 
     var monitor = new SemaphoreSlim(1); 
     monitor.Wait(); 
     var form = new Insured(); 
     form.ObserveControlEvents<DataGridView>(
      "dataGridView1", 
      "DataSourceChanged", 
      (sender, args) => 
      { 
       Trace.WriteLine("Occured in delegate"); 
       monitor.Release(); 
      }); 
     form.ClickButton("btnSearch"); 
     monitor.Wait(); 
    } 
} 

我希望這可以幫助別人。