Get Output from my process

Question

I am querying the version of sql server using sqlcmd (from my app) and would like to display the info, say, on a rich text box, how do i go about it, here's the code:

        Process proc = new Process();
        proc.StartInfo.UseShellExecute = false;
        proc.StartInfo.RedirectStandardOutput = true;
        proc.StartInfo.FileName = "sqlcmd";
        proc.StartInfo.Arguments = @"-U sa -P somepassword -q 'SELECT @@VERSION' -S (localhost)\InstanceName";
        proc.Start();    


        StringBuilder q = new StringBuilder();
        while (!proc.HasExited)
        {
            q.Append(proc.StandardOutput.ReadToEnd());

        }
        string r = q.ToString();
        rtbCheckVersion.Text = r;
        proc.WaitForExit();

possible duplicate of [How to redirect process output to System.String](http://stackoverflow.com/questions/3829749/how-to-redirect-process-output-to-system-string). Actually this question (in various variations, has been asked a couple of times. Hint: with your `while (!proc.HasExited)` you are over-complicating things. — Christian.K, May 07 '12 at 10:31
Why you are using sqlcmd, why not simply connect to DB and execute 'SELECT @@VERSION' ? — Antonio Bakula, May 07 '12 at 10:31
Hi Christian, you're actually right, it is sort of a duplicate. But how come am i not getting any output? — coder16, May 07 '12 at 10:32
@Antonio, connecting to DB is too much work for such a simple query... — coder16, May 07 '12 at 10:33
@coder16 Connecting to DB and performing the query yourself is actually much less CPU overhead than starting `sqlcmd`. I would say **"Redirecting process output is too much work for such a simple query"**. — Anders Marzi Tornblad, May 07 '12 at 10:38

score 2 · Answer 1 · edited May 23 '17 at 10:08

2

since you have to execute a sql script, you could use SqlConnection and SqlCommand to get the output instead of starting a separated process.

check this answer and other answers in this question for some examples: https://stackoverflow.com/a/949933/559144

edited May 23 '17 at 10:08

Community

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1

answered May 07 '12 at 10:30

Davide Piras

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Thanks, Davide, great answear. but how do i get it right by using my technique? – coder16 May 07 '12 at 10:36

score 0 · Answer 2 · answered May 07 '12 at 10:36

0

I see you don't want to use SqlConnection and SqlCommand...
I'm not sure, but it could be that your process exits before you get output.
Try this:

proc.Start();    
string s = proc.StandardOutput.ReadToEnd();

answered May 07 '12 at 10:36

Marco

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@coder16, you may also want to enable and read from `StandardError` in case "something" did not run as expected. – Tung May 07 '12 at 10:45
@Marco, got it: "Sqlcmd: '@@VERSION'': Unexpected argument. Enter '-?' for help.\r\n" looks like my arguments are incorrect... – coder16 May 07 '12 at 10:59

Get Output from my process

2 Answers2