Mark Arteaga

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

[DllImport("coredll.dll")]
private static extern int SystemParametersInfo(uint uiAction, 
uint uiParam, string pvParam, uint fWiniIni);

private const uint SPI_GETOEMINFO = 258;

public static bool IsEumlator()
{
    string szOEMInfo = " ";
    string strOEMInfo = "";

    // Get OEM Info
    int ret = SystemParametersInfo(SPI_GETOEMINFO, szOEMInfo.Length, szOEMInfo, 0);
    if (ret != 0)
    {
        strOEMInfo = szOEMInfo.Substring(0, szOEMInfo.IndexOf('\0'));
        return strOEMInfo.Equals("Microsoft DeviceEmulator");
    }
    else
        throw new Exception("Unable to determine");
}

Using Silverlight for Windows Phone 7, you can now use the System.Environment.DeviceType which simply returns Unknown, Emulator or Device.

    if (System.Environment.DeviceType == DeviceType.Emulator)
    {
        MessageBox.Show("You are running on the emulator.");
    }
    else if (System.Environment.DeviceType == DeviceType.Unknown)
    {
        MessageBox.Show("You are running on an unknown device.");
    }
    else
    {
        MessageBox.Show("You are running on a device");
    }

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!