C / C++ / MFC

23-May-09 0:58

I am deleting a record from the table and then using the MoveNext()fucntion to move to the next record in the recordset.Below is the code for that.
How do i do that using the code below ??

<pre>void CSimpdbView::OnRecordsDelete()
{
CSimpdbDoc* pDoc=GetDocument();
_CommandPtr pCmd;
pCmd.CreateInstance(__uuidof(Command));
_ParameterPtr paramIsbn;
CString strIsbn;

CEdit* pEdit = (CEdit*)GetDlgItem(IDC_ISBN);
pEdit->GetWindowText(strIsbn);
_bstr_t sqlQuery("DELETE FROM lib WHERE ISBN = ?");

int val = MessageBox("This deletes the record.Continue ?",NULL,MB_OKCANCEL);
if(val == IDOK)
{
try
{
pCmd->ActiveConnection = pDoc->m_pConnection;
pCmd->CommandText=sqlQuery;

paramIsbn = pCmd->CreateParameter("strIsbn",adVarChar,adParamInput,-1,vtMissing);
paramIsbn->Value = (_variant_t)strIsbn;
pCmd->Parameters->Append(paramIsbn);

pCmd->Execute(NULL,NULL,adCmdText);
MessageBox("Record Deleted !",NULL,MB_OK);
pRs->MoveNext(); //Should move to the next reccord !
}

catch(_com_error &e)
{
TRACE( "Error:%08lx.\n", e.Error());
TRACE( "ErrorMessage:%s.\n", e.ErrorMessage());
TRACE( "Source:%s.\n", (LPCTSTR) _bstr_t(e.Source()));
TRACE( "Description:%s.\n", (LPCTSTR)_bstr_t(e.Description()));
}
catch(...)
{
TRACE("\n****Unhandled Exception****\n");
}
}
}

Help Please . Confused | :confused:

Stuart Dootson23-May-09 1:55

23-May-09 1:55

What's wrong with the recordset's Delete method[^]? (Well, possibly this[^], it's something you need to check).

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

vital_parsley200023-May-09 2:26

23-May-09 2:26

OMG!!

I m sorry i forgot to add the question to the post!!

Well, in the above code i m able to delete the record but i want it to show the next record once the record is deleted.For which i m using the pRs->MoveNext() method.
What i want to know is how do i do this ??

Stuart Dootson23-May-09 3:13

23-May-09 3:13

I think using the Delete method of the Recordset allows you to do just that without needing to worry about delete commands or anything like that. I guess you just need to open the recordset as read-write? This page[^] may provide more reassurance about that.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

vital_parsley200023-May-09 4:11

23-May-09 4:11

But isnt there a way where i could delete the record using sql query and then move to the next record and show it on GUI ? Confused | :confused:

Stuart Dootson23-May-09 4:24

23-May-09 4:24

I've just looked at your code properly - I presume pRS is a member of a class somewhere whose cursor points at the current record that a) you're displaying, and b) you want to delete?

If so, then this should work:

void CSimpdbView::OnRecordsDelete() 
{
   int val = MessageBox("This deletes the record.Continue ?",NULL,MB_OKCANCEL);
   if(val == IDOK)
   {
      try
      {
         pRs->Delete(adAffectCurrent);
         MessageBox("Record Deleted !",NULL,MB_OK);
         pRs->MoveNext(); //Should move to the next reccord !
      }

      catch(_com_error &e)
      {
         TRACE( "Error:%08lx.\n", e.Error());
         TRACE( "ErrorMessage:%s.\n", e.ErrorMessage());
         TRACE( "Source:%s.\n", (LPCTSTR) _bstr_t(e.Source()));
         TRACE( "Description:%s.\n", (LPCTSTR)_bstr_t(e.Description()));
      }
      catch(...)
      {
         TRACE("\n****Unhandled Exception****\n");
      }
   }
}

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

vital_parsley200023-May-09 4:46

23-May-09 4:46

In my code i deleted the record using sql query as you can see,and i have declared :

ResultsetPtr pRs;

in the View.h file.So it is globally accessible.So in that case (making changes to the code you gave),i have to call the sql query

select * from lib_details where ISBN = ? ;

and then insert the parameter using command object and append function
and then call pRs->Open()
and then pRs->Delete(adAffectCurrent);
and then pRs->MoveNext(); //as you have mentioned in your code

I hope what i have mentioned is right.

But instead of this can i delete the record using sql query and then move to the next record ? if this is possible how can it be done ? and i guess it would be easier . Blush | :O

Stuart Dootson23-May-09 5:04

23-May-09 5:04

vital_parsley2000 wrote:
But instead of this can i delete the record using sql query and then move to the next record ?

The term 'next record' has no meaning unless you've selected a bunch of records into a recordset. What I thought you had done (and would suggest you do) is select the records you are interested in (using a SELECT statement) into a record-set. Then the user can delete a record if they choose to (using the record-set's delete method, as I showed you) and you can move on to the record-set's next record. The record-set would be declared at class scope, so it is persistent across event handlers. Something like this (obviously this is a bare-bones sketch of what you'd use):

class MyDoc
{
   // other declarations
   _RecordsetPtr pRs;
  void SelectRecords(parameters) { /* create and initialise record-set */ }
};

class MyView
{
   void DisplayRecord() { /* Display the current record in GetDocument()->pRs; }
   void OnNextRecordButtonPressed() ( GetDocument()->pRs->MoveNext(); DisplayRecord(); }
   void OnDeleteRecordButtonPressed() ( GetDocument()->pRs->Delete(adAffectCurrent); OnNextRecordButtonPressed(); }
};

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

[Message Deleted]

vital_parsley200024-May-09 21:07

24-May-09 21:07

[Message Deleted]

Stuart Dootson25-May-09 0:40

25-May-09 0:40

If the objcore.cpp in your MFC is like mine, you've got a bad object somewhere. Look at a) what the assertion in objcore say, b) which of your objects it is acting on, c) the call stack - that will show where in your program the assertion originates.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

vital_parsley200025-May-09 5:09

25-May-09 5:09

Thanx for ur replies.Appreciate your help Big Grin | :-D

CueBanner in vc6

ganesh.dp23-May-09 0:49

ganesh.dp

23-May-09 0:49

how can i add "cue banner" facility to cedit in vc++ 6.0

Re: CueBanner in vc6

Stuart Dootson23-May-09 1:51

Dial up Network Connection status dialog.

23-May-09 1:51

To use the in-built system ones (present on XP or later so long as you have a suitable manifest in your executable[^]), then download the latest SDK compatible with VC6[^] and use something like this:

// Let's presume your CEdit control is called editControl
   editControl.SendMessage(EM_SETCUEBANNER, (WPARAM)FALSE, (LPARAM)(L"< enter text here >"));

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

birajendu23-May-09 0:39

birajendu

23-May-09 0:39

Hi,

If we go to Control panel->Network Connections , system will show all the network connections available for that system. Right click on any connection icon we will see status option in that context menu. I would like to know how can i invoke that status menu from my application for a specific dial-up connection?

Thanks in advance...

birajendu
CyberG India
Delhi
India

Re: Dial up Network Connection status dialog.

Hamid_RT23-May-09 1:26

Hamid_RT

23-May-09 1:26

See Showing Dial-up Connection Status Window[^]
.

Of one Essence is the human race
thus has Creation put the base
One Limb impacted is sufficient
For all Others to feel the Mace
(Saadi )

Re: Dial up Network Connection status dialog.

birajendu23-May-09 1:53

birajendu

23-May-09 1:53

Thanks, That is gr8. But Like to lunch the windows dialogbox which we used get from clicking status menu item. I dont need a custom dialog.

birajendu
CyberG India
Delhi
India

Socket programming

rajeshbhushetty23-May-09 0:34

rajeshbhushetty

23-May-09 0:34

Hello
I want to receive some data from client (browser) to my server(mfc applicatoin)using socket.I need some reference too. Please help.

Re: Socket programming

Rajesh R Subramanian23-May-09 0:42

Rajesh R Subramanian

23-May-09 0:42

Please learn to use the search feature.

Have a look at Programming Windows TCP Sockets in C++ for the Beginner[^]

It is a crappy thing, but it's life -^ Carlo Pallini

Re: Socket programming

Stuart Dootson23-May-09 1:41

23-May-09 1:41

This[^] is a good starter guide to network programming with sockets.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

using Hotkeys

jalsa G22-May-09 21:14

jalsa G

22-May-09 21:14

Hello

How to use f1 as hotkey ?

Jalsa

Rajesh R Subramanian22-May-09 21:28

Rajesh R Subramanian

22-May-09 21:28

By pressing it. More info here[^]

It is a crappy thing, but it's life -^ Carlo Pallini

jalsa G22-May-09 21:48

jalsa G

22-May-09 21:48

if ( GetAsyncKeyState ( VK_F1) & SHRT_MAX )
puts ( "F1 key is pressed" );

Jalsa

Rajesh R Subramanian22-May-09 23:06

Rajesh R Subramanian

22-May-09 23:06

Why can't you give some information that may help the people who attempt to answer your query?

What kind of application is it? (I've to guess it by looking at puts Roll eyes | :rolleyes:

)
What are you trying to achieve? Add help to your application?
Or just trap the F1 key? Where do you want to be notified? Only in your app or anywhere?

It is a crappy thing, but it's life -^ Carlo Pallini

Hamid_RT22-May-09 23:32

Hamid_RT

22-May-09 23:32

You need to else statement? Big Grin | :-D

Of one Essence is the human race
thus has Creation put the base
One Limb impacted is sufficient
For all Others to feel the Mace
(Saadi )