你如何知道一个控件是否来自一个类

Question

我有一个控件列表(_controlList),从控件列表中我想得到从给定类派生的控件.所以我的代码看起来像这样.

List<Control> _controlList = new List<Control>();

public Control[] ControlsThatIsA(Type soughtType)
{
  List<Control> result = new List<Control>();
  foreach (Control control in _controlList)
  {
// This would have been nice but doesn't compile
//////////////
//  if (control.GetType() is soughtType)
    {
      result.Add(control);
    }
  }
return result.ToArray();
}

有什么想法吗.我没有传入Type,它可能是类的字符串名称

Answer 1

首先,我可能会使用泛型:

public T[] ControlsOfType<T>() where T : Control
{
  List<T> result = new List<T>();
  foreach (Control control in _controlList)
  {
    if (control is T)
    {
      result.Add((T)control);
    }
  }
  return result.ToArray();
}

或者在.NET 3.5中:

return _controlList.OfType<T>().ToArray();

如果你需要使用Type,那么IsAssignableFrom特别是你的朋友:

if(soughtType.IsAssignableFrom(control.GetType())) {
   //...
}