Using Process.Start to run a .NET 6 dll

December 13, 2022

I want to start a process with some arguments out of a .NET 6 console application to run a dll that was also created in .NET 6.

When I try to cmd:
> dotnet myPath/myApp.dll testParam everything works fine

but when I try to use:

Process process = new Process();
        process.StartInfo.FileName = "dotnet myPath/myApp.dll";
        process.StartInfo.WorkingDirectory = "myPath";
        process.StartInfo.Arguments = "testParam";
        process.StartInfo.UseShellExecute = false;
        process.Start();

I’m getting the following exception

System.ComponentModel.Win32Exception: ‘An error occurred trying to start process ‘dotnet myPath/myApp.dll testParam’ with working directory ‘myPath’.

As I try to copy and paste the string out of the exception into cmd, it works just fine.

I tried to set the working directory, as explained here

>Solution :

Please see the documentation https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.process?view=net-6.0

var dllPath = Path.Combine("myPath", "myApp.dll");

using Process process = new Process();
process.StartInfo.FileName = "dotnet"; // Append ".exe" if on windows
process.StartInfo.Arguments = $"{dllPath} testParam";
process.StartInfo.UseShellExecute = false;
process.Start();