waitforexit

[hrishi321]

Hi, Another problem of mine. I run a process(say a calculator) from a button click. Now I want to resume(do nothing/disable) the form till the user finishes the process ie till he closes the calculator. I am using waitforexit like below(not the exact code) dim p as new process p.startinfo="calc" p.waitforexit() p.start() It works fine,.But sometime it gives an error in the line(p.waiforexit) saying that p has not been allocated any process (not the exact error, but with similar measning) Please help me Thanks in advance

[Dave Kreskowiak]

This is because your Waiting for the process to exist before you start the process! You can't wait for something to exit if it doesn't exist yet! Switch those two lines around and it'll work.

A guide to posting questions on CodeProject[^]
Dave Kreskowiak Microsoft MVP Visual Developer - Visual Basic
     2006, 2007, 2008

[hrishi321]

thanks for your reply i think u r mistaking me. its waitforexit not exist...

[Henry Minute]

himangshu123 wrote:

i think u r mistaking me.

No but you are mistaking him. Dave Kreskowiak correctly pointed out that your code waits for exit before it starts. It should start and then wait for exit;

p.waitforexit()
p.start()

switch those two lines round then all should be well. Incidentally in your OP you stated that the code you posted was not the exact code, and the error message was not the exact error message. In this case it doesn't seem to have made any difference, but you really should (particularly for error messages), give the exact wording.

Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”

[hrishi321]

oh apologise me... my mistake... actually I have done the same...i didnt cut copy the code so that mistake came...sorry... please help me

[hrishi321]

sorry.... code is dim p as new process p.startinfo="calc" p.start() p.waitforexit() this was my actual code still the problem arise

[Dave Kreskowiak]

A very minor typo.

A guide to posting questions on CodeProject[^]
Dave Kreskowiak Microsoft MVP Visual Developer - Visual Basic
     2006, 2007, 2008

[Dave Kreskowiak]

Next time, copy and paste the code. Don't retype it from memory. You'll get the order of statements wrong and quite possibly not convey some minor detail that makes all the difference to whether your code runs or not. Between the call to .Start and .WaitForExit, add the line p.WaitForInputIdle(). This will force your code to wait for the app to start.

A guide to posting questions on CodeProject[^]
Dave Kreskowiak Microsoft MVP Visual Developer - Visual Basic
     2006, 2007, 2008