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Re: Monitoring Files - Disk Access

Anonymous27-Oct-02 4:02

Anonymous

27-Oct-02 4:02

Thank you soo much. Smile | :)

The only thing is though to make that monitor every fixed hard drive i would probably have to do a recursive search through each directory, which would be a major hit on performance for something thats running the background.

Any suggestions?

(Ive posted this without looking at the code so i may be able to work it for myself.)

Thanks.

Gav

Re: Monitoring Files - Disk Access

Anonymous27-Oct-02 4:05

Anonymous

27-Oct-02 4:05

Forgot my password!

Ive just found out that code only works on Windows NT / 2000 and XP. Which isnt any use to me as im on Windows 98 SE.

Gutted Frown | :(

Thanks again for the information but if anyone has anymore information etc i would be very grateful!

Gav

Re: Monitoring Files - Disk Access

Ravi Bhavnani27-Oct-02 4:09

Ravi Bhavnani

27-Oct-02 4:09

I think you'd need to do the recursive search once. After that, you may be able to use this class[^] to add/remove directories of interest. It would be cool if you wrote a new version of Wes Jones' CDirectoryChangeWatcher class that supported recursive watches!

/ravi

Let's put "civil" back in "civilization"
http://www.ravib.com
ravib@ravib.com

Re: Monitoring Files - Disk Access

Anonymous27-Oct-02 7:46

Anonymous

27-Oct-02 7:46

Thanks again for your help.

Damn... this is going to take some coding!

Does the code you suggested work with Windows 98?

Thanks for all your input.

Any other suggestions from other people?

Gav

Re: Monitoring Files - Disk Access

Ravi Bhavnani27-Oct-02 9:32

Ravi Bhavnani

27-Oct-02 9:32

Anonymous wrote:
Does the code you suggested work with Windows 98?

Sorry, I haven't used these classes.

/ravi

Let's put "civil" back in "civilization"
http://www.ravib.com
ravib@ravib.com

Serializing and class hierarchy

Conan Ua Diarmaid27-Oct-02 3:32

Conan Ua Diarmaid

27-Oct-02 3:32

hi,
I have a base class say,CEmployee and other derived classes say CManager,CDirector etc.
CEmployee is CObject derived for getting all those features from CObject.
Now,I have a list of employees (CEmployee*) in stl list<> and I serialize them.Everything is fine while storing,but while loading i cannot get the correct class and will just read CEmployee.
How to use the RTTI for serialization.

-Conan

Re: Serializing and class hierarchy

Ravi Bhavnani27-Oct-02 3:41

Ravi Bhavnani

27-Oct-02 3:41

See this series[^] of articles.

/ravi

Let's put "civil" back in "civilization"
http://www.ravib.com
ravib@ravib.com

Yah, read that but not enough info.

Con27-Oct-02 4:24

Con

27-Oct-02 4:24

Yah, read that but not enough info.

Re: Yah, read that but not enough info.

Ravi Bhavnani27-Oct-02 4:30

Ravi Bhavnani

27-Oct-02 4:30

When you save the objects to disk, the first thing you should serialize is the object's signature (or RTTI information), followed by the object itself. When you read back the object from disk, use a ClassFactory pattern to construct an object of the appropriate type, then serialize (read in) the object.

/ravi

Let's put "civil" back in "civilization"
http://www.ravib.com
ravib@ravib.com

Re: Class Factory

Con27-Oct-02 4:35

Con

27-Oct-02 4:35

:-DSorry if i am a pain but its bit tricky at the moment.

Should I implement the class factory .If we use CObList or something,everything gets done from CArchive.But i am using stl list<> holding pointers.How to implement it?

Re: Class Factory

Ravi Bhavnani27-Oct-02 4:45

Ravi Bhavnani

27-Oct-02 4:45

Write the employee list to disk like this:

for (each employee in list) {
  CString strSignature;
  *pArchive << pEmployee->getSignature();
  pEmployee->serialize (pArchive);
}

When you read the object from disk, do this:

CString strSignature;
strSignature << *pArchive;
CEmployee* pEmployee = EmployeeClassFactory.createObject (strSignature);
if (pEmployee == NULL) {
   // bad object read in
} else {
   pEmployee->serialize (pArchive);
}

// Add pEmployee to list - doesn't matter if it's STL or not

/ravi

Let's put "civil" back in "civilization"
http://www.ravib.com
ravib@ravib.com

Re: Last One

Con27-Oct-02 4:52

Con

27-Oct-02 4:52

So this means I will have to write my own class factory.
Why can't ar>> pEmployee do the job here when a similar thing can do it for CObList in the MSDN sample DrawCli.

Thanx for answering

Re: Last One

Ravi Bhavnani27-Oct-02 10:38

Ravi Bhavnani

27-Oct-02 10:38

I haven't seen the DRAWCLI sample. If it works by using the streaming operator >>, it's because the Employee class's >> operator is doing the work of a class factory.

/ravi

Let's put "civil" back in "civilization"
http://www.ravib.com
ravib@ravib.com

Re: Serializing and class hierarchy

Gero Gerber27-Oct-02 3:44

Gero Gerber

27-Oct-02 3:44

Before storing each object save an identifier for each object. Use CObject::GetRuntimeClass() and store CRuntimeClass::m_lpszClassName before actually saving an object. While loading read the string and create an appropriate instance of the class and serialize it.

Gero

Re: Serializing and class hierarchy

Con27-Oct-02 4:25

Con

27-Oct-02 4:25

How to load a pointer into the list using CRuntimeClass name?

Re: Serializing and class hierarchy

Gero Gerber27-Oct-02 4:43

Gero Gerber

27-Oct-02 4:43

How do you exactly serialize the list currently?

Gero

Re: Like this

Con27-Oct-02 4:55

Con

27-Oct-02 4:55

just walk all te elements using an iterator and call Serialize() against each element while storing but create a new CEmployee and serialize that and load.

Re: Like this

Gero Gerber27-Oct-02 5:04

Gero Gerber

27-Oct-02 5:04

Then do it like this:

// Storing

for each element in the list
ar.WriteString(object.GetRuntimeClass()->m_lpszClassName);
object.Serialize(ar);

// Loading

CString strType;
CBaseType *pType = NULL;

for number of objects stored in archive
ar.ReadString(strType);

// Check which object was stored based on strType
// and load it
pType = new CStoredType();
((CStoredType *)pType)->Serialize(ar);

// insert (CStoredType *)pType into list

Hope this helps,
Gero

phisical view of a dictionary

includeh1027-Oct-02 3:28

includeh10

27-Oct-02 3:28

we all know how to develop a collection of List or Array, i mean: develop real classes of them for using.

but i have no idea how to develop a collection of dictionary or map or bag etc.

i think a dictionary is based on List or Array with key sorted.

is the guess correct? can u give me some clues?
thx

includeh10

Re: phisical view of a dictionary

Conan Ua Diarmaid27-Oct-02 4:58

Conan Ua Diarmaid

27-Oct-02 4:58

yah,
thats where you begin and later optimise the operations.Ues a map rather then a list of pairs.The map can do all the dirty work for you and do it better in most cases.
Conan

Re: phisical view of a dictionary

includeh1027-Oct-02 7:20

includeh10

27-Oct-02 7:20

????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????

i don't like a reply with no looking and no thinking

includeh10

DocTemplates - Printing and Previewing

Jerry Bogota27-Oct-02 3:24

Jerry Bogota

27-Oct-02 3:24

Hello,
How to get the print feature for different doc templates.
Just handling id_file_print doesn't do anything.Could any one help by listing the steps or something.
Bye.

Re: DocTemplates - Printing and Previewing

Roger Allen28-Oct-02 1:53

Roger Allen

28-Oct-02 1:53

In MFC, its the view which handles the printing of data from a document. All CView derived class's have the OnPrint() member function, which gets called once per page of output. You have to implement that printing code in this function for your document template view class.

Take a look at the examples in the printing section here.

Roger Allen
Sonork 100.10016

I have a terminal disease. Its called life!

Help context sensitive help in VC++

B4u27-Oct-02 3:21

B4u

27-Oct-02 3:21

hi evry1

i have got a strange prob ,whenever i select context sensitive help option from appwizard , the project created does not builds,it just hangs and is unable to create help files.i tried directly exec the "makehelp" file
but it says that some hcw file is missing,.
I have even tried reinstllg VC++ but to no avail.
pls i need urgent help as myproject rquires this feature

thnx
bhushan Confused | :confused:

Re: Help context sensitive help in VC++

Roger Allen28-Oct-02 2:00

Roger Allen

28-Oct-02 2:00

The makehelp.bat file generate the yourprojectname.hm file used by the help compiler to match topic ID's with the dialog/control ID's in your application. You only need to run this .bat file when you add new ID's to your project etc.

HCW.EXE is the microsoft supplied help compiler. On my PC this is installed in Program files\Microsoft visual studio\common\tools. You may need to correctly setup your VS environment variables so that it can find the tool when you come to compile your help file.

Goto Tools:Options in VS studio. Sleect Directories and the sub option Executable files. Make sure the path top the location of your installed tools directory is present.

Roger Allen
Sonork 100.10016

I have a terminal disease. Its called life!

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.