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Dictionary objectI have a dictionary object, then I create a new dictionary object and sets
it equal to my original, then I pass the new dictionary object to a function that changes some of my values - but then my original dictionary also gets changed and that was not the intention, can someone explain to me why it behaves that way and how do I avoid it, så I van have different dictionary objects? Thanks Betina Betina Andersen wrote:
> I have a dictionary object, then I create a new dictionary object and sets Looks like it's because the argument is passed to the function ByRef,> it equal to my original, then I pass the new dictionary object to a function > that changes some of my values - but then my original dictionary also gets > changed and that was not the intention, can someone explain to me why it > behaves that way and how do I avoid it, så I van have different dictionary > objects? > meaning that instead of passing 'the thing' into the function you just get a reference to 'the thing'. So any changes you make to 'the thing' will be reflected in the original. I haven't used ASP for a long time, but you need to change the argument to be ByVal, which means you get a *copy* of 'the thing', like in the following code: <% function monkey(byval thing) monkey = thing & "<br/>" thing = thing + 1 end function dim a a = 1 response.write monkey(a) response.write a %> You should see two 1s if it's worked as expected. Take the 'byval' away and you get 1 and 2, because the argument is Byref again and the function was able to monkey around with the original variable. "Betina Andersen" <b**@invalid.com> wrote in message My very old copy of MSDN says...news:O1fWkyhsGHA.3548@TK2MSFTNGP04.phx.gbl... > I have a dictionary object, then I create a new dictionary object and sets > it equal to my original, then I pass the new dictionary object to a function > that changes some of my values - but then my original dictionary also gets > changed and that was not the intention, can someone explain to me why it > behaves that way and how do I avoid it, så I van have different dictionary > objects? "Generally, when you use Set to assign an object reference to a variable, no copy of the object is created for that variable. Instead, a reference to the object is created. More than one object variable can refer to the same object. Because these variables are references to (rather than copies of) the object, any change in the object is reflected in all variables that refer to it." I would guess that the following occurs... dim x dim z set x = CreateObject("Scripting.Dictionary") 'x contains (for instance) the number 536474 'which is a memory address that points to the dictionary object set z = CreateObject("Scripting.Dictionary") 'z contains a pointer to a different object e.g. the memory address 73462 set z = x 'z now contains 536474, and so points to the original object - same as x I think you need something like this... set z = copydict(x) function copydict(x) dim j, k, i, z set z = CreateObject("Scripting.Dictionary") k = x.Keys i = x.Items for j = 0 to x.Count - 1 z.Add k(j), i(j) next set copydict = z end function -- roger roger wrote:
> "Generally, when you use Set to assign an object reference to a variable, no I guess that's why these things have .clone() methods (see ADO> copy of the object is created for that variable. Instead, a reference to the > object is created. More than one object variable can refer to the same > object. Because these variables are references to (rather than copies of) > the object, any change in the object is reflected in all variables that > refer to it." > recordset). Except in this case, where it would be useful. ;)
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"Bobbo" <robin***@gmail.com> wrote in message I've not seen any objects in common use that have clone method of the typenews:1154355620.482208.241320@p79g2000cwp.googlegroups.com... > > roger wrote: > > > "Generally, when you use Set to assign an object reference to a variable, no > > copy of the object is created for that variable. Instead, a reference to the > > object is created. More than one object variable can refer to the same > > object. Because these variables are references to (rather than copies of) > > the object, any change in the object is reflected in all variables that > > refer to it." > > > > I guess that's why these things have .clone() methods (see ADO > recordset). Except in this case, where it would be useful. ;) > desired by the OP. The clone method of a recordset allow a new filter and seek position to be created independant of the orginal recordset object. However the underlying data remains the same if you change the data in one the changes are visible in the other.
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