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Pass an object by Reference to another form?

Hi,
I would like to know whether there's any way for me to pass an object by
reference to another form?

Regards
Vanessa
Nov 20 '05
11 7776


Jon Skeet wrote:
Rick <rrquick@nosp am-com> wrote:
Why have the DataSet in Form A at all? Why not have an independant class
(a singleton) that holds the DataSet and shares it across Form A and
Form B?

I don't see why a singleton is needed here at all. I would suggest
creating a new instance of the independent class, and passing a
reference to that instance to the constructors of both Form A and Form
B. Using a singleton avoids the need for that reference, but could
prove restrictive later on.


True, I did think about that but then I can't think of a reason why (in
her situation) she would want to keep an instance being passed around
for a convenient class wrapping the DataSet. Her requirement was to keep
it consistent by making any change in another form reflect back to the
other (or others). Since it's only a DataSet and not a user defined
class which could grow into something more meaningful or useful,
requiring separate instances, I believe a singleton is probably the
best, clean choice. Then again, that's only my honest opinion :)

Rick

Nov 20 '05 #11
Rick <rrquick@nosp am-com> wrote:
I don't see why a singleton is needed here at all. I would suggest
creating a new instance of the independent class, and passing a
reference to that instance to the constructors of both Form A and Form
B. Using a singleton avoids the need for that reference, but could
prove restrictive later on.
True, I did think about that but then I can't think of a reason why (in
her situation) she would want to keep an instance being passed around
for a convenient class wrapping the DataSet.


Well, there's nothing to say for sure that there couldn't be multiple
instances of forms A and B, with each pair sharing a single DataSet.
Her requirement was to keep
it consistent by making any change in another form reflect back to the
other (or others). Since it's only a DataSet and not a user defined
class which could grow into something more meaningful or useful,
requiring separate instances, I believe a singleton is probably the
best, clean choice. Then again, that's only my honest opinion :)


I tend to shy away from using Singletons unless it's a real design
decision to go for them, rather than just as a convenience.

--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
Nov 20 '05 #12

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