In some instances when developing your Windows Phone 7 app using Silverlight you may want to know if your code is running within the emulator or within a real device. For example in my previous post on shake detection on Windows Phone 7 I didn’t want to create an new AccelerometerWithShakeDetection object if it was running in the emulator since the hardware is not available in the emulator.
In .NET Compact Framework it was a little bit of a pain to get this information as you have to PInvoke and have to know the native calls to get this information as follows
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[<span style="color: #2b91af">DllImport</span>(<span style="color: #a31515">"coredll.dll"</span>)] <span style="color: blue">private static extern int </span>SystemParametersInfo(<span style="color: blue">uint </span>uiAction, <br /><span style="color: blue">uint </span>uiParam, <span style="color: blue">string </span>pvParam, <span style="color: blue">uint </span>fWiniIni); <span style="color: blue">private const uint </span>SPI_GETOEMINFO = 258; <span style="color: blue">public static bool </span>IsEumlator() { <span style="color: blue">string </span>szOEMInfo = <span style="color: #a31515">" "</span>; <span style="color: blue">string </span>strOEMInfo = <span style="color: #a31515">""</span>; <span style="color: green">// Get OEM Info </span><span style="color: blue">int </span>ret = SystemParametersInfo(SPI_GETOEMINFO, szOEMInfo.Length, szOEMInfo, 0); <span style="color: blue">if </span>(ret != 0) { strOEMInfo = szOEMInfo.Substring(0, szOEMInfo.IndexOf(<span style="color: #a31515">'\0'</span>)); <span style="color: blue">return </span>strOEMInfo.Equals(<span style="color: #a31515">"Microsoft DeviceEmulator"</span>); } <span style="color: blue">else throw new </span><span style="color: #2b91af">Exception</span>(<span style="color: #a31515">"Unable to determine"</span>); } |
Using Silverlight for Windows Phone 7, you can now use the System.Environment.DeviceType which simply returns Unknown, Emulator or Device.
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<span style="color: blue">if </span>(System.<span style="color: #2b91af">Environment</span>.DeviceType == <span style="color: #2b91af">DeviceType</span>.Emulator) { <span style="color: #2b91af">MessageBox</span>.Show(<span style="color: #a31515">"You are running on the emulator."</span>); } <span style="color: blue">else if </span>(System.<span style="color: #2b91af">Environment</span>.DeviceType == <span style="color: #2b91af">DeviceType</span>.Unknown) { <span style="color: #2b91af">MessageBox</span>.Show(<span style="color: #a31515">"You are running on an unknown device."</span>); } <span style="color: blue">else </span>{ <span style="color: #2b91af">MessageBox</span>.Show(<span style="color: #a31515">"You are running on a device"</span>); } |
Again, no more PInvokes since it’s not supported and the code is a lot easier to write and maintain.
So far in my working with Windows Phone 7 and Silverlight I haven’t required PInvoke functionality so far. We’ll see what happens in the future as the SDK gets out of CTP and we get customer projects but so far so good!
Funny I read this post by Raymond Chen just a few days back,
"If you can detect the difference between an emulator and the real thing, then the emulator has failed"
http://blogs.msdn.com/b/oldnewthing/archive/2010/05/19/10013611.aspx
🙂