C / C++ / MFC

Re: Saving a Document with values from dynamic array?

2-Apr-02 6:28

Hio.. i am trying to store a CObArray into my document class.. but not having any luck.. I have another class i have written myself which serializes a CObArray into a file, but i can't seem to figure out the correct way to do it in a CDocument as it is not possible to put ar >> CObArrayVar ..

any suggestions? for example, if i want a user to enter in any number of strings, and be able to save it to a document and open it back up, how would i handle the dynamic size?

thanks for any suggestions!

-dz

Ravi Bhavnani2-Apr-02 6:43

Re: Saving a Document with values from dynamic array?

2-Apr-02 6:43

See "Serializing a homogenous collection class" in this article.

/ravi

"There is always one more bug..."
http://www.ravib.com
ravib@ravib.com

dazinith2-Apr-02 8:07

Re: Saving a Document with values from dynamic array?

2-Apr-02 8:07

i hate to seem dense.. BUT... Smile | :)

ok, i should serialize the signature, then the version, then i should store the number of items in the CObArray.. then i should store each of the CObjects? you say serialize the object, then serialize the data members.. i should be able to just serialize my CObject derived class right? i shouldn't have to specify every data member of it right?

oh ya, im assuming i should do a for loop to CObArray.GetSize() to store each item?

thanks for all of your help lately!

-dz

Ravi Bhavnani2-Apr-02 8:22

Re: Saving a Document with values from dynamic array?

2-Apr-02 8:22

dazinith wrote:
i should be able to just serialize my CObject derived class right? i shouldn't have to specify every data member of it right?

Yes, you should serialize the signature, version, size of the CObArray, and each object in the CObArray. The objects in turn should serialize themselves by writing out their signature, version and data members.

Part 3 of my tutorial is crying out for code examples. I haven't had the time to post them but definitely plan to do this when I have some spare time.

/ravi

"There is always one more bug..."
http://www.ravib.com
ravib@ravib.com

dazinith2-Apr-02 8:41

Re: Saving a Document with values from dynamic array?

2-Apr-02 8:41

well, i got it to work where i store each of the members of the class in the loop, but i would much rather just store the CObject derived object directly.. the problem is that if i try to do:
ar << objMyObject

it tells me there is nothing that can handle the << . My CObject derived class has the serialization function. I have tried casting it to a CObject and storing that, but i think im storing the pointer value and not the actual data.. i think i got it to save, but when i load it gives errors for unexpected file format.. i have left out the versioning just for simplicity.. i just need to know how to load and store all of the values from the m_oaStringList (which is of CObArray type)

if (ar.IsStoring())
{
ar << m_oaStringList.GetSize(); // store the size of the array

// loop through and store all data members
for (i = 0; i < m_oaStringList.GetSize(); i++)
{
CObject* pObj = m_oaStringList.GetAt(i);
ar << (&pObj);
}
}
else // is loading
{
int n; // load the size of the array
ar >> n;

// loop through and load all data members
for (i = 0; i < n; i++)
{
CObject* pObj = (CObject*)new CTestObj();
ar >> pObj;
}
}

thanks!

-dz

Ravi Bhavnani2-Apr-02 9:08

Re: Saving a Document with values from dynamic array?

2-Apr-02 9:08

You're close. There are 2 changes I suggest you make:

Write a serialize (CArchive& ar) method for your object. The method will simply serialize the data members of the object (using the << and >> operators). Call this serialize() method instead of doing "ar << pObj" or "ar >≶ pObj". In other words, do "pObj->serialize (ar);" instead.
When deserializing (reading in), you should set the size of the CObArray before adding members to it. Then, as you deserialize each object (again by simply calling its serialize() method to read itself in), put the object in the CObArray's appropriate slot.

/ravi

"There is always one more bug..."
http://www.ravib.com
ravib@ravib.com

dazinith2-Apr-02 11:33

Re: Saving a Document with values from dynamic array?

2-Apr-02 11:33

thank you so much for your help today.. i got the code to do what i want.. and thats be able to store and load a document based off of CObArray.. I just did a simple object, but now i feel i could use it for a much larger object.. here is the finished code if you want to use it to update that article.. again thanks for the help!

p.s. if you do use this as an example you might want to change the var's as m_oaStringList seems like a CStringArray, but is a CObArray.. thanks so much!

void CDocumentTestDoc::Serialize(CArchive& ar)
{
int i;

if (ar.IsStoring())
{
// store the size of the array
int n = m_oaStringList.GetSize();
ar << n;

// loop through and store all data members
for (i = 0; i < m_oaStringList.GetSize(); i++)
{
CTestObj* pObj = (CTestObj*)m_oaStringList.GetAt(i);
pObj->Serialize(ar);
}

}
else // is loading
{
// load the size of the array
int n;
ar >> n;
m_oaStringList.SetSize(n);

// loop through and load all data members
for (i = 0; i < n; i++)
{
CTestObj* pObj = new CTestObj();
pObj->Serialize(ar);
m_oaStringList.SetAt(i,pObj);
}
}
}

-dz

Ravi Bhavnani2-Apr-02 11:50

Re: Saving a Document with values from dynamic array?

2-Apr-02 11:50

dazinith wrote:
i got the code to do what i want..

Excellent!! Glad I could be of help! Now I really must get off my posterior and update the article! Smile | :)

/ravi

"There is always one more bug..."
http://www.ravib.com
ravib@ravib.com

dazinith3-Apr-02 3:10

Re: Saving a Document with values from dynamic array?

3-Apr-02 3:10

is it possible to use these same ideas to store a CObArray inside of another CObArray? for example, if the CObArray im serializing now contains a data variable which is also a CObArray with its own serialize function, when the top level CObArray gets serialized does this in turn call the serialization of the lower object?

-dz

Ravi Bhavnani3-Apr-02 3:15

how to create a imput mask?

3-Apr-02 3:15

Absolutely!

The top level CObArray doesn't know how to serialize its content objects. It just tells each one "go serialize yourself". If the content object is another CObArray, it goes about serializing itself by storing its signature, version, item count, and then asks each of its objects to serialize themselves.

/ravi

"There is always one more bug..."
http://www.ravib.com
ravib@ravib.com

jafrazee2-Apr-02 5:39

jafrazee

2-Apr-02 5:39

i have a Cedit control that hold phone#.
i can create a display mask to show the phone # like(111)111-1111.
but how can i create this as an imput mask for automatically place the () and- while typing and also not let them type alpha char?

thank you.

C^hris L^osinger2-Apr-02 5:37

C^hris L^osinger

2-Apr-02 5:37

try looking in the Edit Controls section of this site. there are probably five or six of them there.

-c

"Do you mind if I smoke?"
"Madam, I don't care if you burn."
-Oscar Wilde

Smaller Animals Software, Inc.

dazinith2-Apr-02 6:38

2-Apr-02 6:38

http://www.codeproject.com/editctrl/maskededit.asp

im using this control, its pretty k-rad, but it seems to have a problem when tabbing from field to field (doesn't highlight the field)..

btw, the typo in the title made me laugh Smile | :)

-dz

Jon Hulatt2-Apr-02 23:37

Jon Hulatt

2-Apr-02 23:37

What the hell is "k-rad" ? is it kEwl sPeEK ??

Sorry to dissapoint you all with my lack of a witty or poignant signature.

dazinith3-Apr-02 3:07