//建立绑定，把绑定到的对象存起来，在表达式解析完成后，外面再监听这些对象的值变化
private void SetBinding(object o, string path)
{
//条件部分不包括
if (path != null)
{
int index = path.IndexOf("[");
if (index != -1)
{
path = path.Substring(0, index);
}
}
//如果建立过绑定，不重复建立
BindInfo info = new BindInfo()
{
Object = o, Path = path
};
if (!this.binds.Contains(info))
{
//把绑定信息存起来，以便检查
binds.Add(info);
//建立绑定关系
Binding b = new Binding();
b.Source = o;
b.Path = new System.Windows.PropertyPath(path);
BindingSlave bs = new BindingSlave();
BindingOperations.SetBinding(bs, BindingSlave.ValueProperty, b);
Bindings.Add(bs);
}
}
/// <summary>
/// 当属性发生变化时，发送Value改变事件，以便多绑定可以监听这个属性的变化。
/// </summary>
/// <param name="depObj">BindingSlave本身</param>
/// <param name="e">属性变化参数</param>
private static void OnValueChanged(DependencyObject depObj, DependencyPropertyChangedEventArgs e)
{
BindingSlave slave = depObj as BindingSlave;
Log.Debug("绑定slave值变了，值为:" + (slave.Value == null ? "null" : slave.Value));
slave.OnPropertyChanged("Value");
}
//监听依赖属性变化，调用属性变化方法
public static void Watch(this DependencyObject source, string dependencyPropertyName, PropertyChangedCallback callback)
{
if (dependencyPropertyName == null || source == null || callback == null)
throw new ArgumentNullException();
Binding binding = new Binding(dependencyPropertyName) { Source = source, Mode = BindingMode.OneWay };
BindingSlave bs = new BindingSlave();
_bindings.Add(bs);
bs.PropertyChanged += (o, e) =>
{
callback(source, new DependencyPropertyChangedEventArgs());
};
BindingOperations.SetBinding(bs, BindingSlave.ValueProperty, binding);
}
//监听集合本身的变化过程
private void MonityCollection(BindingSlave bs)
{
//开始要监听集合中对象的属性变化过程
foreach (object obj in (IEnumerable)bs.Value)
{
if (obj is GeneralObject)
{
(obj as GeneralObject).DynamicPropertyChanged += PropertyChangedHandler;
}
}
//监听集合本身的变化过程
(bs.Value as INotifyCollectionChanged).CollectionChanged += (o1, e1) =>
{
Assign(bs.Result);
//reset时，监听集合自身所有对象变化
if (e1.Action == NotifyCollectionChangedAction.Reset)
{
foreach (object obj in (IEnumerable)o1)
{
if (obj is GeneralObject)
{
(obj as GeneralObject).DynamicPropertyChanged += PropertyChangedHandler;
}
}
}
//监听集合中新增对象的属性变化
if (e1.NewItems != null)
{
foreach (object obj in e1.NewItems)
{
if (obj is GeneralObject)
{
(obj as GeneralObject).DynamicPropertyChanged += PropertyChangedHandler;
}
}
}
//删除集合中移除对象的属性变化
if (e1.OldItems != null)
{
foreach (object obj in e1.OldItems)
{
if (obj is GeneralObject)
{
(obj as GeneralObject).DynamicPropertyChanged -= PropertyChangedHandler;
}
}
}
};
}
//建立绑定，把绑定到的对象存起来，在表达式解析完成后，外面再监听这些对象的值变化
private void SetBinding(object o, string path)
{
//条件部分不包括
if (path != null)
{
int index = path.IndexOf("[");
if (index != -1)
{
path = path.Substring(0, index);
}
}
//如果建立过绑定，不重复建立
BindInfo info = new BindInfo() {Object = o, Path = path};
if (!this.binds.Contains(info))
{
//把绑定信息存起来，以便检查
binds.Add(info);
//建立绑定关系
Binding b = new Binding();
b.Source = o;
b.Path = new System.Windows.PropertyPath(path);
BindingSlave bs = new BindingSlave();
BindingOperations.SetBinding(bs, BindingSlave.ValueProperty, b);
Bindings.Add(bs);
}
}
public void OnLoaded(object o, RoutedEventArgs e)
{
//避免重复工作
_targetObject.GetType().GetEvent("Loaded").RemoveEventHandler(_targetObject, handler);
handler = null;
//对表达式进行解析，在绑定发生变化时，调用表达式执行
//可以对一组表达式工作，表达式之间用'|or|'分割
string[] strs = Str.Split(new String[] { "|or|" }, StringSplitOptions.RemoveEmptyEntries);
foreach (string str in strs)
{
Program prog = new Program(str, _targetObject, true);
Delegate result = prog.Parse(prog.Exp);
Result = result;
Expression = prog.exp;
//如果目标是一个代理，直接把编译结果给目标
if (_targetProperty != null && _targetProperty.PropertyType == typeof(Delegate))
{
_targetProperty.SetValue(_targetObject, result, null);
return;
}
//如果有事件，则只是在事件发生时才执行表达式。第一次默认及属性变化都不执行。
if (prog.Events.Count == 0)
{
//先执行一次默认赋值过程，然后当属性值改变时，再调用每个赋值过程
Assign(result);
foreach (BindingSlave bs in prog.Bindings)
{
//把BS保存起来，以免丢失
bs.Result = result;
_bindings.Add(bs);
bs.PropertyChanged += (o1, e1) =>
{
if (e1.PropertyName == "Value")
{
BindingSlave _bs = (BindingSlave)o1;
Assign(bs.Result);
//如果是集合本身变了，要监听集合内容的变化过程
if (_bs.Value is INotifyCollectionChanged)
{
MonityCollection(_bs);
}
}
};
//如果绑定到了集合，要监听集合变化过程
if (bs.Value is INotifyCollectionChanged)
{
MonityCollection(bs);
}
}
}
//执行事件触发时的表达式计算过程
foreach (ObjectEvent ei in prog.Events)
{
if (ei.Event.EventHandlerType == typeof(SelectionChangedEventHandler))
{
ei.Event.AddEventHandler(ei.Object, new SelectionChangedEventHandler((o1, e1) => { Assign(result); }));
}
else if (ei.Event.EventHandlerType == typeof(RoutedEventHandler))
{
ei.Event.AddEventHandler(ei.Object, new RoutedEventHandler((o1, e1) => { Assign(result); }));
}
else if (ei.Event.EventHandlerType == typeof(AsyncCompletedEventHandler))
{
ei.Event.AddEventHandler(ei.Object, new AsyncCompletedEventHandler((o1, e1) => { Assign(result); }));
}
else if (ei.Event.EventHandlerType == typeof(MouseButtonEventHandler))
{
ei.Event.AddEventHandler(ei.Object, new MouseButtonEventHandler((o1, e1) => { Assign(result); }));
}
else if (ei.Event.EventHandlerType == typeof(RoutedPropertyChangedEventHandler <object>))
{
ei.Event.AddEventHandler(ei.Object, new RoutedPropertyChangedEventHandler <object>((o1, e1) => { Assign(result); }));
}
else if (ei.Event.EventHandlerType == typeof(PopulatingEventHandler))
{
ei.Event.AddEventHandler(ei.Object, new PopulatingEventHandler((o1, e1) => { Assign(result); }));
}
else if (ei.Event.EventHandlerType == typeof(RoutedPropertyChangedEventHandler <Boolean>))
{
ei.Event.AddEventHandler(ei.Object, new RoutedPropertyChangedEventHandler <Boolean>((o1, e1) => { Assign(result); }));
}
else if (ei.Event.EventHandlerType == typeof(NotifyCollectionChangedEventHandler))
{
ei.Event.AddEventHandler(ei.Object, new NotifyCollectionChangedEventHandler((o1, e1) => { Assign(result); }));
}
else if (ei.Event.EventHandlerType == typeof(EventHandler))
{
ei.Event.AddEventHandler(ei.Object, new EventHandler((ol, el) => { Assign(result); }));
}
else
{
throw new Exception("不支持这种事件类型：" + ei.Event.EventHandlerType);
}
}
}
}
