Threadsichere und generische Kommunikation Windows Forms

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106

using System.Security.Permissions;

[assembly: PermissionSetAttribute(SecurityAction.RequestMinimum, Name = "FullTrust")]
namespace Cyrons.Forms
{
   using System.Reflection;
   using System.Windows.Forms;

   /// <summary>
   /// Bietet Funktionen für den threadsicheren Zugriff auf Objekte von Windows Forms Controls.
   /// </summary>
   public class ControlCommunicationsManager
   {
      #region Delegates

      private delegate void MethodCaller<ControlType>(
         ControlType control,
         string methodName,
         params object[] parameters)
         where ControlType : Control;

      private delegate object PropertyValueReaderCallback<ControlType>(
          ControlType control, string propertyName)
          where ControlType : Control;

      private delegate void PropertyValueWriterCallback<ControlType, PropertyType>(
          ControlType control, string propertyName, PropertyType value)
          where ControlType : Control;

      #endregion Delegates
      #region Methods

      /// <summary>
      /// Invokes a control method call.
      /// </summary>
      /// <typeparam name="ControlType">The type of the control.</typeparam>
      /// <param name="control">The control.</param>
      /// <param name="methodName">Name of the method.</param>
      /// <param name="parameters">Parameters array for the method to be called.</param>
      public void InvokeControlMethodCall<ControlType>(
         ControlType control,
         string methodName, params object[] parameters)
         where ControlType : Control
      {
         if(control.InvokeRequired)
         {
            MethodCaller<ControlType> callerDelegate = InvokeControlMethodCall;
            control.Invoke(callerDelegate, new object[] { control, methodName, parameters });
         }
         else
         {
            MethodInfo method = control.GetType().GetMethod(methodName);
            method.Invoke(control, parameters);
         }
      }

      /// <summary>
      /// Invokes reading of a control property.
      /// </summary>
      /// <typeparam name="ControlType">The type of the control.</typeparam>
      /// <param name="control">The control.</param>
      /// <param name="propertyName">Name of the property.</param>
      /// <returns></returns>
      public object InvokeControlPropertyReader<ControlType>(
         ControlType control,
         string propertyName)
         where ControlType : Control
      {
         if(control.InvokeRequired)
         {
            PropertyValueReaderCallback<ControlType> cb = InvokeControlPropertyReader;
            return control.Invoke(cb, new object[] { control, propertyName });
         }
         PropertyInfo property = control.GetType().GetProperty(propertyName);
         return property.GetValue(control, null);
      }

      /// <summary>
      /// Invokes writing to a control property.
      /// </summary>
      /// <typeparam name="ControlType">The type of the control.</typeparam>
      /// <typeparam name="PropertyType">The type of the property.</typeparam>
      /// <param name="control">The control.</param>
      /// <param name="propertyName">Name of the property.</param>
      /// <param name="value">The value.</param>
      public void InvokeControlPropertyWriter<ControlType, PropertyType>(
          ControlType control,
          string propertyName,
          PropertyType value)
          where ControlType : Control
      {
         if(control.InvokeRequired)
         {
            PropertyValueWriterCallback<ControlType, PropertyType> cb = InvokeControlPropertyWriter;
            control.Invoke(cb, new object[] { control, propertyName, value });
         }
         else
         {
            PropertyInfo property = control.GetType().GetProperty(propertyName);
            property.SetValue(control, value, null);
         }
      }

      #endregion
   }
}