How To Run A Downloaded File From Memory?

Question

Possible Duplicate:
Load an EXE file and run it from memory using C#

I am using the WebClient class to download a .exe from a web server. Is there a way that I can run the .exe without saving it to disk first?

For the purpose of completeness let me show you what I have so far.

Here is the code I use to start the download:

WebClient webClient = new WebClient();
webClient.DownloadDataCompleted += new DownloadDataCompletedEventHandler(webClient_DownloadDataCompleted);
webClient.DownloadDataAsync(new Uri("http://www.somewebsite.com/calc.exe"));

And in the (webClient_DownloadDataCompleted) method I simply grab the bytes from the parameter e:

private void webClient_DownloadDataCompleted(object sender, DownloadDataCompletedEventArgs e)
{
    Byte[] downloadedData = e.Result;
    // how to run this like a .exe?
}

Thank you.

I am not sure. My program cannot make any assumptions about the type of .exe. — Jan Tacci, Jan 07 '13 at 19:06
Generic case is covered by duplicate with explanation why you have to store and run from disk. — Alexei Levenkov, Jan 07 '13 at 19:09

score 2 · Accepted Answer · edited May 23 '17 at 11:59

2

If your .exe is a .NET program, you can load an assembly and run its entry point.

Otherwise, while there are ways to do it, I can't see the problem with saving a file in temporary directory and running it from there which is so much less painful.

edited May 23 '17 at 11:59

Community

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answered Jan 07 '13 at 19:06

Dan Abramov

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Yes. Saving it to the system temp directory is probably what I will end up doing. – Jan Tacci Jan 07 '13 at 19:07
@Jan: If you have such option, definitely go with it. Running an arbitrary PE file is no easy thing as you can see. – Dan Abramov Jan 07 '13 at 19:08

score 1 · Answer 2 · edited May 23 '17 at 11:50

1

Have a look at this thread. I think you can solve it with VirtualAlloc

Is it possible to execute an x86 assembly sequence from within C#?

If your byte array contains a .Net assembly you should be able to do this:

Assembly assembly = AppDomain.Load(byteArray)
Type typeToExecute = assembly.GetType("ClassName");
Object instance = Activator.CreateInstance(typeToExecute);

edited May 23 '17 at 11:50

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answered Jan 07 '13 at 19:07

Moriya

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How To Run A Downloaded File From Memory?

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