How to create a WaitHandle on a native HANDLE? nickdu 12/28/2008 2:34:01 PM I'm using interop (PInvoke) to call a method (FindFirstPrinterChangeNotification) which returns an event handle. I would like to stay as much as possible in managed code so I want to get this native event handle into a managed WaitHandle so I can call one of the WaitHandle's Wait() methods. How do I do this? The only way I see is to either: 1. Create an EventWaitHandle instance and then set the SafeWaitHandle property. The problem with this route is that it will first create an event object that I don't need. 2. Derive a class from WaitHandle so that I can get access to its protected constructor which accepts a SafeWaitHandle. Is there some other way? I was hoping there was an exposed way to create a WaitHandle from a native event handle. -- Thanks, Nick nicknospamdu[ at ]community.nospam remove "nospam" change community. to msn.com

Re: How to create a WaitHandle on a native HANDLE? "Mark Salsbery [MVP]" <MarkSalsbery[MVP][ at ]newsgroup.nospam> 12/28/2008 5:04:56 PM "nickdu" <nicknospamdu[ at ]community.nospam> wrote in message news:B6238BF5-DA74-41BA-B588-699CE21DD702[ at ]microsoft.com... [Quoted Text] > I'm using interop (PInvoke) to call a method > (FindFirstPrinterChangeNotification) which returns an event handle. I > would > like to stay as much as possible in managed code so I want to get this > native > event handle into a managed WaitHandle so I can call one of the > WaitHandle's > Wait() methods. How do I do this? > > The only way I see is to either: > > 1. Create an EventWaitHandle instance and then set the SafeWaitHandle > property. The problem with this route is that it will first create an > event > object that I don't need. > > 2. Derive a class from WaitHandle so that I can get access to its > protected > constructor which accepts a SafeWaitHandle. > I'd personally go with option 2, not necessarily just to get access to a protected constructor, but because the WaitHandle class is designed to wrap a native OS handle. Seems like a simple, clean solution to me. Mark -- Mark Salsbery Microsoft MVP - Visual C++ > Is there some other way? I was hoping there was an exposed way to create > a > WaitHandle from a native event handle. > -- > Thanks, > Nick > > nicknospamdu[ at ]community.nospam > remove "nospam" change community. to msn.com

RE: How to create a WaitHandle on a native HANDLE? hongyes[ at ]online.microsoft.com ("Hongye Sun [MSFT]") 12/29/2008 7:14:11 AM Hi Nick, Thanks for your posting. Personally, I agree with Mark that option #2 is the cleanest resolution for this issue. I don't know any other better ways to do this job. For your reference, here is an examle and it is similar to option #1: http://www.codeproject.com/KB/printing/qPrintcomponent2.aspx The difference is that it is using ManualResetEvent and ThreadPool.RegisterWaitForSingleObject. Hope it helps. Regards, Hongye Sun (hongyes[ at ]online.microsoft.com, remove 'online.') Microsoft Online Community Support Delighting our customers is our #1 priority. We welcome your comments and suggestions about how we can improve the support we provide to you. Please feel free to let my manager know what you think of the level of service provided. You can send feedback directly to my manager at: msdnmg[ at ]microsoft.com.   ================================================== Get notification to my posts through email? Please refer to http://msdn.microsoft.com/en-us/subscriptions/aa948868.aspx#notifications.   Note: MSDN Managed Newsgroup support offering is for non-urgent issues where an initial response from the community or a Microsoft Support Engineer within 2 business day is acceptable. Please note that each follow up response may take approximately 2 business days as the support professional working with you may need further investigation to reach the most efficient resolution. The offering is not appropriate for situations that require urgent, real-time or phone-based interactions. Issues of this nature are best handled working with a dedicated Microsoft Support Engineer by contacting Microsoft Customer Support Services (CSS) at http://msdn.microsoft.com/en-us/subscriptions/aa948874.aspx ================================================== This posting is provided "AS IS" with no warranties, and confers no rights.