Question

I have a C# console executable started within a DOS command process.

I need to be able to execute DOS commands from the C# executable (specifically I need to be able to SET variables) and have the variables persist such that the rest of the DOS process can reference them.

ie:

Start DOS process
-> C# executes a SET command to set UserVariable
-> DOS process can ECHO %UserVariable%

Due to performance reasons I cannot write the set command to a dos script. In fact, I cannot have any file I/O at all.

Can anyone help?

Answer 1

If you are running a C# app from a dos script and wishing to use variables set in the app afterwards from the script, I don’t know how to do that for just the context of that script from within C#, the other answers here show you for the machine itself but I appreciate you need something with a less permanent scope.

A meta-programming workaround this could be to:

• Call the C# app from a DOS FOR loop
• From the C# app, output to the console SET commands
• Use the for loop to execute the app output

The calling DOS script would look like this:

FOR /F "tokens=* delims=" %%A IN ('MyApp.exe') DO ( 
   %%A
)

The Console output from MyApp.exe would need to be in the form:

SET UserVariable1=UserValue1
SET UserVariable2=UserValue2

And then each of the output lines would be executed by the calling FOR loop and the variables would then exist in the context of the calling script.