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You can use FullTrustProcessLauncher class to launch your .exe file from your UWP app. The methods in this class may only be called by packages that have the runFullTrust capability. To use this class, we recommend that you add a Windows Application Packaging Project to your solution. You can follow the steps below to launch your .exe file.
1.You need to add "Windows Desktop Extensions" reference in your uwp project. Right click the References-> Add Reference->Universal Windows->Extensions-> add Windows Desktop Extensions".
2.If your .net program and uwp app in the same solution, right-click your solution, add a Windows Application Packaging Project, then add your uwp app and .net program as Application references to the Packaging project to package them in one package. If they are in the different solution, you can copy .exe file to your UWP Application start up folder (for example: Assets folder), then you just need to reference your uwp in the Packaging project.
3.Add the windows.fullTrustProcess extension in your Windows Application Packaging Project's manifest within the <Application> node.
<Extensions>
<desktop:Extension
xmlns:desktop="http://schemas.microsoft.com/appx/manifest/desktop/windows10"
Category="windows.fullTrustProcess"
Executable="ConsoleApp2\ConsoleApp2.exe" />
</Extensions>
Note that, please specify path of your exe file located in the Executable property. If the .net program and uwp app in the same solution, input "ConsoleApp2\ConsoleApp2.exe". If you just copy the .exe file into your uwp app, input "Assets\ConsoleApp2.exe".
4.Use the FullTrustProcessLauncher class to launch your .exe file.
if (ApiInformation.IsApiContractPresent("Windows.ApplicationModel.FullTrustAppContract", 1, 0))
{
await FullTrustProcessLauncher.LaunchFullTrustProcessForCurrentAppAsync();
}
5.Run your Windows Application Packaging Project.