Internet Explorer catches my Edit Control's BackSpace, arrow keys? - C / C++ / MFC Discussion Boards

Opening a CRecordset derived class problem

Munkijo19-Jun-02 3:22

19-Jun-02 3:22

I am currently working on a system that uses an Access database to store a list of url's waiting to be processed. I need to be able to add to, and amend the database, and so, I have derived a class from the CRecordset class called CURLRecordset using the classwizard.

In my application, I can succesfully open a CDatabase object in order to connect to the database, but when it comes to opening the actual recordsets associated with it:

/*
CURLRecordset* unparsed_urls;
CDatabase* db;
CString sql;
*/

unparsed_urls = new ( CUnparsed ) ( db );
sql.Format ( "SELECT * FROM urls WHERE status = %d;", STATUS_NOT_CRAWLED );
unparsed_urls->Open ( CRecordset::snapshot, (LPCTSTR)sql );

I get the following exception:
"Invalid character value for cast specification on column number 2 (urladdress)"

I have traced the source of the exception to the final move() function call in the CRecordset class's Open() method, but I have no idea how to deal with it. My database schema is as follows:

TABLE urls =
(
long urlid (PRIMARY KEY)
VARCHAR(256) urladdress
long status
long level
long keywordid
long sourceid
)

The header file for the CURLRecordset class is as follows:

class CURLRecordset : public CRecordset
{
public:
CURLRecordset(CDatabase* pDatabase = NULL);
DECLARE_DYNAMIC(CURLRecordset)

// Field/Param Data
//{{AFX_FIELD(CURLRecordset, CRecordset)
long m_keywordid;
long m_level;
long m_sourceid;
long m_status;
CString m_urladdress;
long m_urlid;
//}}AFX_FIELD

// Overrides
// ClassWizard generated virtual function overrides
//{{AFX_VIRTUAL(CURLRecordset)
public:
virtual CString GetDefaultConnect(); // Default connection string
virtual CString GetDefaultSQL(); // Default SQL for Recordset
virtual void DoFieldExchange(CFieldExchange* pFX); // RFX support
//}}AFX_VIRTUAL

// Implementation
#ifdef _DEBUG
virtual void AssertValid() const;
virtual void Dump(CDumpContext& dc) const;
#endif
};

Any help will be greatly appreciated!

Re: Opening a CRecordset derived class problem

Chad Koehler19-Jun-02 7:18

Chad Koehler

19-Jun-02 7:18

I think the problem may be in your DoFieldExchange() function...I can't think of anywhere else that the problem could be.

Blowfish Encryption

Senkwe Chanda19-Jun-02 3:06

Senkwe Chanda

19-Jun-02 3:06

Hi guys, there's a nice article here on CP with a C++ implementation of the Blowfish algorithm for encrypting files. The examples given however are a bit simplistic and I can't seem to get it to encrypt a text file. Has anyone done that yet?

Senkwe

Just another wannabe code junky

Re: Blowfish Encryption

C^hris L^osinger19-Jun-02 3:18

C^hris L^osinger

19-Jun-02 3:18

0. initialize the cipher
1. open input file
2. open output file (binary mode)
3. while (you haven't read the whole input file)
3a. get a block of text from the input
3b. encrypt it
3c. write it
4. close both

the last block will probably require padding to the cipher's block size

-c

Cheap oil. It's worth it!

Image Processing - just like mom used to make.

Re: Blowfish Encryption

Senkwe Chanda19-Jun-02 3:23

Senkwe Chanda

19-Jun-02 3:23

C^hris L^osinger wrote:
3a. get a block of text from the input
3b. encrypt it
3c. write it

You mean I should append each encrypted block of text to the output file?

Just another wannabe code junky

Re: Blowfish Encryption

C^hris L^osinger19-Jun-02 3:33

C^hris L^osinger

19-Jun-02 3:33

yes.

thought it's not so much "append" as it is "write". "append" implies the file already exists (and is closed) and you're going to add more to it after re-opening it.

but, the idea is to read, encrypt then write one block at a time.

-c

Cheap oil. It's worth it!

Image Processing - just like mom used to make.

Re: Blowfish Encryption

Senkwe Chanda19-Jun-02 3:35

Senkwe Chanda

19-Jun-02 3:35

Will do, thanks for the help Chris

Senkwe

Just another wannabe code junky

Internet Explorer catches my Edit Control's BackSpace, arrow keys?

S.Maharajan19-Jun-02 2:58

S.Maharajan

19-Jun-02 2:58

I put an OCX control window. I put an Edit box derived from CEDit. In Edit box, if I press backspace, message will not posted to my active edit box, instead goes to IE. Similarly, Arrow Keys, Home, End Messages are captured by IE. How this can be avoided? How I Edit smoothly?

ATL Service

Hans Ruck19-Jun-02 2:32

Hans Ruck

19-Jun-02 2:32

I've created an ATL service which offers an interface. In a test program i successfuly get a pointer to the interface but i can't see the service among the listed ones in the "Services" application.
Do you know how could i bring the service in the list as i can manually start and stop it? What exactly means the post-build registering step?

rechi

Re: ATL Service

19-Jun-02 2:42

You need to register the service.

<servicename> -service

By default ATL registers it as a local server using servicename /RegServer

Re: ATL Service

Hans Ruck19-Jun-02 3:18

Hans Ruck

19-Jun-02 3:18

Thanx!
One more question: i saw in ServiceMain this call: LogEvent(_T("Service stopped")); . Is it about a loggin' system? If true, where is the log file?

rechi

Re: ATL Service

Michael P Butler19-Jun-02 3:30

Michael P Butler

19-Jun-02 3:30

You can see these events in the Event Viewer under Administrative Tools on Window NT systems.

Michael Smile | :)

"Eureka" is Greek for "This bath is too hot"

Transform and Lighting Capability on Graphics Card

19-Jun-02 2:20

Hi all, I'm using DirectX and am trying to see whether my graphics card can use the IID_IDirect3DTnLHalDevice ref before committing my application to it (where a nasty fail would happen if it couldn't). I have used the EnumDevices Callback function to obtain a D3DEVICEDESC7 pointer containing information about my Graphics card and am trying to check the dwDevCaps variable for the D3DDEVCAPS_HWTRANSFORMANDLIGHT cap by using:

if (!(lpdEnumDevice->dwDevCaps & D3DDEVCAPS_HWTRANSFORMANDLIGHT))
return Error;

lpdEnumDevice is the correct structure, but this test always returns false! I have tried using the IID_IDirect3DTnLHalDevice id at CreateDevice time and it works! so I know it must support it. What am I doing wrong? I have a nVidia GeForce 2 Ultra (Gainward spec) graphics card.

Oh and thanks for the response Mike but the D3DDEVCAPS_HWTRANSFORMANDLIGHT was introduced in version 7 of the DirectX SDK (according to Microsofts instructions), it has a DWORD value of 65536 whilst my dwDevCaps member variable has a value of 1361, which is obviously why it is returning false. But why is this value so low? Do I hav to call a GetCaps() function or something? or re-inialise the D3DEVICEDESC7 structure in the callback function somehow? The Microsoft SDK articles seem to suggest I'm doing it the right way (don't they???), but it still fails to succeed.

How do I even know if its trying to access my nVidia card?

Ta all,
Alan.

Re: Transform and Lighting Capability on Graphics Card

Alan Chambers19-Jun-02 9:50

Alan Chambers

19-Jun-02 9:50

Well call me stupid! What I did was working all along! The thing is the EnumDevices callback function CYCLES through all the compatible devices on the system, one by one and applies each function test to each device. I had only debugged the initial function application which enumerates the RGB Software compatibility (hence the test failing). Upon pressing ctrl + F10 the callback tests the next device available, the HAL, and by pressing ctrl + F10 again it tests the TnLHAL, which is the device I wish to use. If the system graphics card does not cater for transforms and lighting, the EnumDevices function will never enumerate this device and so never return true to the test I mentioned earlier. Hope this helps anyone out there with the same problem.

Alan.

"When I left you I was but the learner, now I am the master" - Darth Vader

MirrorBlt?

Dov Sherman19-Jun-02 2:16

Dov Sherman

19-Jun-02 2:16

Is there a function similar to BitBlt which can be used to take a DIB Bitmap in memory and draw it to device context flipped horizontally or vertically?

Re: MirrorBlt?

C^hris L^osinger19-Jun-02 2:28

C^hris L^osinger

19-Jun-02 2:28

no, i don't think there is.

-c

Cheap oil. It's worth it!

Image Processing - just like mom used to make.

Re: MirrorBlt?

Christian Graus19-Jun-02 2:53

Christian Graus

19-Jun-02 2:53

No, but if you pass reversed co-ordinates to BitBlt, you'll get the result you are after.

Christian

I am completely intolerant of stupidity. Stupidity is, of course, anything that doesn't conform to my way of thinking. - Jamie Hale - 29/05/2002

Half the reason people switch away from VB is to find out what actually goes on.. and then like me they find out that they weren't quite as good as they thought - they've been nannied. - Alex, 13 June 2002

Re: MirrorBlt?

C^hris L^osinger19-Jun-02 3:44

C^hris L^osinger

19-Jun-02 3:44

example please Frown | :(

edit
ahh... not BitBlt like you said, but StretchBlt, like he said. it all makes sense now.

-c

Cheap oil. It's worth it!

Image Processing - just like mom used to make.

Re: MirrorBlt?

Dov Sherman19-Jun-02 3:47

Dov Sherman

19-Jun-02 3:47

Ah! I see. By using StretchBlt, right? Thank you. It seems to work perfectly.

Setting & Getting ItemData

Steve L.19-Jun-02 1:37

Steve L.

19-Jun-02 1:37

I have a tree control, m_treeItem, and I'm trying to set and get data to only one item in the control. CItemInfo is the class that I'm storing my data in. Heres my code:

void CMyView::AddItem()
{
	HTREEITEM hMainItem;
	HTREEITEM hSubItem;

	//create object and assign variables
	CItemInfo *itemInfo = new CItemInfo;
	itemInfo->m_strName = "A Name";
	itemInfo->m_strAge = "An Age";
	itemInfo->m_strSex = "A Sex";

	//add the tree items	
	hMainItem = m_treeItem.InsertItem( "First Item" );
	hSubItem = m_treeItem.InsertItem( "Second Item", hMainItem, TVI_SORT );

	//set the item data
	m_treeItem.SetItemData( hSubItem, (DWORD)itemInfo );
	
	//delete the object
	delete itemInfo;
}

void CMyView::OnSelChange( some variables I dont use )
{
	//make sure the selected item is at the end of the tree
	if( m_treeItem.GetChildItem(m_treeItem.GetSelectedItem())==NULL )
	{
		//get the data
		DWORD dwData = m_treeItem.GetItemData( m_treeItem.GetSelectedItem() );
		CItemInformation *itemInfo = (CItemInformation *)dwData;
		//display the data
		MessageBox( itemInfo->m_strName );
		MessageBox( itemInfo->m_strAge );
		MessageBox( itemInfo->m_strSex );
	}
}

The problem is that all of the MessageBox's display the same thing and its always about 3 lines of garbage. What am I doing wrong? Thanks in advanced.

-Raffi

Re: Setting & Getting ItemData

Steve L.19-Jun-02 1:42

Steve L.

19-Jun-02 1:42

Ok, after some screwing around, I found that if I comment out the line "delete itemInfo" it works. However I get memory leaks, so my new question is, do I have to store each CItemInfo object that I make in a list or something before deleting it?

-Raffi

Re: Setting & Getting ItemData

Michael P Butler19-Jun-02 1:56

Michael P Butler

19-Jun-02 1:56

SetItemData takes a pointer to the allocated memory, so that when you called delete the pointer was no longer valid.

You need to keep the pointer active until you've finished. You could just loop through all your items and delete the pointer returned from GetItemData before you destroy the control. Or like you suggest you could have a list which gets deleted later. I tend to keep a vector of pointers and then free up the memory in the destructor.

Michael Smile | :)

"Eureka" is Greek for "This bath is too hot"

Re: Setting & Getting ItemData

Steve L.19-Jun-02 2:00

Steve L.

19-Jun-02 2:00

Thanks a lot Smile | :)

-Raffi

Re: Setting & Getting ItemData

_Magnus_19-Jun-02 1:50

_Magnus_

19-Jun-02 1:50

Can you really do this?
<bold>CItemInfo *itemInfo = new CItemInfo*;
Should it not be
<bold>CItemInfo *itemInfo = new CItemInfo;

Otherwise you would allocate a new pointer.
...at least that's what i think.

/Magnus

Re: Setting & Getting ItemData

Steve L.19-Jun-02 1:52

Steve L.

19-Jun-02 1:52

I had it correct in my code, just a mistake when writing the question.

-Raffi

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