how do I raise an event?
I use VB 6.0 I see that there are multiple places that I have to put code to handle events and
I keep getting it wrong. I want to do I have a form that has a button. When that button is clicked,
another program that is running at the same time as the first program catches a "p1_button_in"
event and turns a light on.
I keep getting it wrong. I want to do I have a form that has a button. When that button is clicked,
another program that is running at the same time as the first program catches a "p1_button_in"
event and turns a light on.
Another easier ways is that when event happens in the 1st program it writes a flag variable to a textfile and
seconds program check that files to do some action.
seconds program check that files to do some action.
if still unclear,
please explain more clearly.
please explain more clearly.
ASKER
I was trying to avoid something like writing to a file. That is going to use disk access and I know that is slow.
I am trying to get the second program to respond immediately to the first programs button click.
I am trying to get the second program to respond immediately to the first programs button click.
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Then Consider writing and readiing from the registry which is very fast.
if you need the code I can supply it here.
if you need the code I can supply it here.
What you're talking about -- I think -- is interprocess communication. There are many ways to do it, one of the most common is the textfile approach that unknown_routine gave you.
The approach that I used under NT 4.0 is to use mailslots. The more modern approach is to use Microsoft Messaging.
You could also use callbacks. It is a slightly more sophisticated approach, but one that requires a fair amount of coding.
http://msdn.microsoft.com/library/en-us/vb98/html/vbsmpCallback.asp?frame=true
You could also do something like store the hWnd of your "lightbulb" program, then when your "click" application starts, you read the hWnd (or title) from whereever you've stored it. When the user clicks the button in the "click" application, you make the "lightbulb" application the foreground application and use SendKeys to send a key sequence that activates your lightbulb.
You could also look at the SendMessage and PostMessage APIs. This would be a very low-level approach.
The approach that I used under NT 4.0 is to use mailslots. The more modern approach is to use Microsoft Messaging.
You could also use callbacks. It is a slightly more sophisticated approach, but one that requires a fair amount of coding.
http://msdn.microsoft.com/library/en-us/vb98/html/vbsmpCallback.asp?frame=true
You could also do something like store the hWnd of your "lightbulb" program, then when your "click" application starts, you read the hWnd (or title) from whereever you've stored it. When the user clicks the button in the "click" application, you make the "lightbulb" application the foreground application and use SendKeys to send a key sequence that activates your lightbulb.
You could also look at the SendMessage and PostMessage APIs. This would be a very low-level approach.
However you can use Message API functions, so when that event happen in the 1st program
they send it to the second and second program turns the light on.