MDAs 是Managed Debugging Assistants的缩写。如果启用了这个功能，当MDAs事件被触发时，会出现一个异常未被处理的对话框，即使没有处于debug状态。
禁止MDAs对话框的产生，参见http://msdn.microsoft.com/en-us/library/d21c150d.aspx
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When an MDA is enabled, it is active even when your code is not executing under a debugger. If an MDA event is raised when a debugger is not present, the event message is presented in an unhandled exception dialog box, although it is not an unhandled exception. To avoid the dialog box, remove the MDA-enabling settings when your code is not executing in a debugging environment. |
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When your code is executing in the Visual Studio integrated development environment (IDE), you can avoid the exception dialog box that appears for specific MDA events. To do that, on the Debug menu, click Exceptions. (If the Debug menu does not contain an Exceptions command, click Customize on the Tools menu to add it.) In the Exceptions dialog box, expand the Managed Debugging Assistants list, and then clear the Thrown check box for the individual MDA. For example, to avoid the exception dialog box for a contextSwitchDeadlock MDA clear the Thrown check box next to its name in the Managed Debugging Assistants list. You can also use this dialog box to enable MDAs. |