first commit

ICSharpCode.TextEditor/Project/Utils/WeakEventHandler.cs

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+using System;
+using System.Diagnostics;
+using System.Reflection;
+
+namespace ICSharpCode.TextEditor.Utils
+{
+    /// <summary>
+    /// http://paulstovell.com/blog/weakevents
+    /// </summary>
+    /// <typeparam name="TEventArgs">The type of the event args.</typeparam>
+    [DebuggerNonUserCode]
+    public sealed class WeakEventHandler<TEventArgs> where TEventArgs : EventArgs
+    {
+        private readonly WeakReference _targetReference;
+        private readonly MethodInfo _method;
+
+        public WeakEventHandler(EventHandler<TEventArgs> callback)
+        {
+            _method = callback.Method;
+            _targetReference = new WeakReference(callback.Target, true);
+        }
+
+        [DebuggerNonUserCode]
+        public void Handler(object sender, TEventArgs e)
+        {
+            var target = _targetReference.Target;
+            if (target != null)
+            {
+                var callback = (Action<object, TEventArgs>)Delegate.CreateDelegate(typeof(Action<object, TEventArgs>), target, _method, true);
+                if (callback != null)
+                {
+                    callback(sender, e);
+                }
+            }
+        }
+    }
+}