SINGLE instance of a Codeunit and assigns

csimoneaux

Form A calls on SINGLE instance of a Codeunit and assigns 'RED' to a global text variable. Form B call an instance of the same Codeunit and assigns the same global variable 'BLUE'. Form A then calls another function in the same Codeunit and retrieves the value of the global variable. What is the value?

a) Red * (chose a) <=
b) Blue (or <=
c) Null
d) You can't do this

Because it is a Single instance I have been told answer is A
BUT
Form A then calls another function in the same Codeunit and retrieves the value of the global variable

So would this make the answer B. I am so confused.

Savatage

read this
How To pass parameters between objects (forms, reports, ...)? Revisited
http://www.mibuso.com/howtoinfo.asp?FileID=9

DenSter

Here's what you do:
Create a single instance codeunit and two forms and start experimenting.

ajhvdb

only B is correct.

are these exam questions?

csimoneaux

Yes, this is an exam question. I do not just want to get answers to questions...I want to understand concepts and logic. Y'all have provided all of this.
Thank you sooooo much. \:D/ \:D/ \:D/

NavIndia

Hi ajhvdb,

How could u say that is the right answer, can u explain it little further :?:

As i think the answer is A) Red. :-k

ajhvdb

the code unit is single instance and uses a global var.
all values in global vars remain in memory until cleared or closing navision.

the last assigned value is blue.

kine

Because it is Single instance, each global variable exists only once. And it is the point. If you assign BLUE in same var, it will be still BLUE. If you assign something other (does not matter from where), it will overwrite this value. It is still same place in memory, same variable... because each global variable defined as this codeunit, leads to same Instance = same point in memory, same object, same global variables etc...

ajhvdb

Excellent explanation, you always wanted to be a teacher ofcourse. 8)