:-J
System developer
Jacob Hjelmer
Thy Data Center Development A/S
S�vej 13b
DK-3460 Birker�d
Denmark
Phone : +45 96 170 470
Fax : +45 45 824 544
URL : http://development.thydatacenter.dk/ <blocked::http://development.thydatacenter.dk/>
_____
From: Matt Benic [mailto:[EMAIL PROTECTED]
Sent: 4. juni 2004 10:52
To: Axapta Dev
Subject: [development-axapta] Passing containers by reference
Hi,
I am currently trying to convert a class-based profiling utility to be able
to make use of global functions. What I want to do is allow the user of the
functions to pass in a (potentially empty) container, and work with that.
So, for example, if a function is passes a parameter container timer I want
to be able to pass it onto my (Global) start function and NOT have to return
a new container, so that the actual container passed in is altered. Is this
possible? At the moment I have the following method in Global:
public static void SUN_StartTimer(container timer)
{
boolean isTiming;
int timeStarted;
int timeElapsed;
int numStarts;
;
[isTiming, timeStarted, timeElapsed, numStarts] = timer;
isTiming = true;
timeStarted = WinAPI::getTickCount();
numStarts++;
timer = conpoke(timer, 1, isTiming, timeStarted, timeElapsed,
numStarts);
}
Which I call in a job as follows:
container con;
;
SUN_StartTimer(con);
print con;
Con always ends up being an empty container. I found the topic below in the
Dev guide, which says that all parameters are passed by value, but I am
kind-of hoping agains hope that there is a way to forcibly pass by
reference, or to specify a parameter as an out parameter. The reason I dont
want to have to actually return the container is that it removes the
possibility of returning something else.
Thanks,
Matt Benic
Axapta Developer
UTi Sun Couriers Division
>From Dev Guide, Axapta Language Reference -> Methods and Variables ->
Parameters and scoping:
Parameters and scoping
The scope rules in X++ state that all methods have their own scope. To use
data from one scope in a different scope, you have to transfer the data into
the other scope, using parameters.
A method can take one or more arguments. Within the scope of the method
these parameters are treated like local variables, initialized with the
value from the parameter in the method-call. Here is an example:
Class declaration
Method methodQ
class Parameter
void methodQ(int aval, real bval)
{
{
int a;
a = aval;
real b;
b = bval;
}
}
Here, a class called Parameter is declared. The class has a method
(methodQ), which takes two parameters, an integer and a real. Four variables
are visible within the scope of methodQ: aval, bval, a and b The a and b
variables are in the scope as they are defined class declaration for the
class.
Assume that ParameterObject is an instance of the Parameter class. If
methodQ is invoked on ParameterObject, like this:
ParameterObject.methodQ(1,2.0);
Then aval is set to the value 1 within the method and the variable bval is
set to 2.0 (it is a real) within the method. The two variables a and b in
the ParameterObject are set to 1 and 2.0, respectively. You can pass the
value of any _expression_ as parameters.
Note that all parameters are passed by value. This means that you can not
change the value of the original variable, but only the local variable in
the method, which is a copy of the original. Here is an example:
Class declaration
Method MethodA
Method MethodB
class ByValue
void MethodA(int i)
void methodB()
{
{
{
}
i = i + 1;
int i = 3;
print i;
print i;
}
this.MethodA(i);
print i;
}
Here, a class ByValue is declared with two methods, MethodA and MethodB.
MethodB has a local variable named i, which is used as a parameter to a call
methodA.
MethodA uses a parameter called i and therefore has a local variable called
i. This local variable has the value of the variable i in methodB (as it is
used as parameter in the call).
The result of invoking MethodB is a print of the value of i in MethodB
before and after MethodA is invoked, and a print of the value of i inside
methodA, which then is the parameter i.
The result of these three prints: 3 4 3
illustrates that the two i variables are two different variables and hence
that MethodA cannot change parameters with effect outside its scope.
[Non-text portions of this message have been removed]
Yahoo! Groups Sponsor
ADVERTISEMENT
click here <http://rd.yahoo.com/SIG=129mj9c75/M=298184.5022502.6152625.3001176/D=groups/S=1705006764:HM/EXP=1086428110/A=2164339/R=0/SIG=11e2d64in/*http:/www.netflix.com/Default?mqso=60183348>
<http://us.adserver.yahoo.com/l?M=298184.5022502.6152625.3001176/D=groups/S=:HM/A=2164339/rand=629612713>
_____
Yahoo! Groups Links
* To visit your group on the web, go to:
http://groups.yahoo.com/group/development-axapta/
* To unsubscribe from this group, send an email to:
[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>
* Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service <http://docs.yahoo.com/info/terms/> .
[Non-text portions of this message have been removed]
| Yahoo! Groups Sponsor | |
|
|
Yahoo! Groups Links
- To visit your group on the web, go to:
http://groups.yahoo.com/group/development-axapta/
- To unsubscribe from this group, send an email to:
[EMAIL PROTECTED]
- Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
