C / C++ / MFC

Re: Convert FILETIME to DATE for ADO ?

24-Aug-01 16:48

You could rip the conversion function off from the MFC sources, its located in "olevar.cpp" : line # 1568 ().

It takes the form;

_AfxOleDateFromTm ( WORD wYear, WORD wMonth, WORD wDay,
   WORD wHour, WORD wMinute, WORD wSecond, DATE & dtDest )

>>> [Update]
You'll also have to use FileTimeToLocalFileTime() and FileTimeToSystemTime() to get a usable date structure ( namely SYSTEMTIME ).

FILETIME fileTime; <br />
<br />
// first convert file time (UTC time) to local time<br />
FILETIME localTime;<br />
FileTimeToLocalFileTime ( &fileTime, &localTime );<br />
<br />
// then convert that time to system time<br />
SYSTEMTIME sysTime;<br />
FileTimeToSystemTime ( &localTime, &sysTime );<br />
<br />
// finaly, convert the system time to DATE type<br />
DATE theDate;<br />
_AfxOleDateFromTm ( stCreate.wYear, stCreate.wMonth, stCreate.wDay,<br />
        stCreate.wHour, stCreate.wMinute, stCreate.wSecond, theDate );

<<< [Update]

Hope this helps.

Have a good one,
Ben Burnett

---------
On the topic of code with no error handling -- It's not poor coding, it's "optimistic" Wink | ;)

Carlos Antollini24-Aug-01 16:55

ADO/ATL problems - my life is hell.

24-Aug-01 16:55

Christian, is easy, convert the FILETIME to COleDateTime then convert the COleDateTime to variant for send to Ado.
Please Christian see in the classes that I sent you, you can see that conversion in the method SetFieldValue....

Cheers!!!! Smile | :)

Carlos Antollini.

Christian Graus24-Aug-01 16:32

24-Aug-01 16:32

I have got filtering working in my recordset but I have some real problems.

1/ I'm not sure how all the string types/functions fit together. I've read the chapter in ATL Internals, but it does not appear to have gelled. I'm trying this:

CComBSTR bstrPath;
(*it)->get_FilePath(&bstrPath);

char * pStr = new char[bstrPath.Length() + 20];
memset(pStr, 0, bstrPath.Length() + 20);

sprintf(pStr, "FilePath = '%s'", (_bstr_t)bstrPath);

MessageBox(NULL, pStr, "", 0);

If I

ATLTRACE(bstrPath)

the value coming in is OK, but the value in the message box is garbage. What am I missing ?

Also, I get my string together like this:

CComBSTR query = "FilePath = '";
query.Append(bstrPath.Copy());  // I initially forgot .Copy(), but it crashes both ways
query.Append("'");

records->Filter = (_bstr_t)query;

Now my string is as I want it to be, but the program crashes on the Filter call. I know I'll get a crash if I pass in bad SQL, but if I pass in the same string verbatim, it works fine. What's wrong with passing in the string as a variable, with the same value ? If I do this:

_bstr_t bquery = "FilePath = 'f:\\biblio1.mdb'";

records->Filter = bquery;

then it appears to work fine, so I presume it's back to me not getting the string thing...

Please help - I'm going mad here.....

Christian

As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet.

Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery.

Carlos Antollini24-Aug-01 16:49

24-Aug-01 16:49

Hi Chris!!!
I Know you.....
What happens with

"FilePath = \"f:\\biblio1.mdb\"";

You can see that I change the ' with ". Some databases are a little ..(I don't know the word) but for example when you use a string that is greatter than 30 characteres is better to use "" and not ''. The SQL Server cut the words in that case.

Big Grin | :-D

Carlos Antollini.

Christian Graus24-Aug-01 17:03

24-Aug-01 17:03

Thanks for trying to help, but it makes no difference if I use single or double quotes - if I use the code that builds a search string, the string is exactly what I would pass in, but if I pass it in manually or through a _bstr_t object I create in one line (_bstr_t t = blah blah ) then it works, but if I build the string using my variable the string is the same and the program crashes.

Christian

As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet.

Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery.

Carlos Antollini24-Aug-01 17:11

24-Aug-01 17:11

When I make a cast to _bstr_t I always use

_bstr_t(str); //when str is for example a CString.

I suspect that you have a problem in the sprintf.
I saw that you pass a parameter making a cast to _bstr_t. I think that is better to make a cast to (LPCTSTR) in the sprinf....
I hope to help you Christian...

Carlos Antollini.

Christian Graus24-Aug-01 17:27

24-Aug-01 17:27

Thanks - now the sprintf is returning the right result and I pass it in like this:

records->Filter = (_bstr_t)pStr;

This still crashes in the Filter() command, although the string going in is still exactly the same string I have previously created in a single line and passed in. I've tried \n and \0 on the end of the string to no avail.

Thanks for helping

Christian

Christian

As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet.

Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery.

Christian Graus24-Aug-01 20:05

24-Aug-01 20:05

It would appear the ADO error only occurs if there are spaces in the field. How do I get around that ? I've put them in quotes (tried single AND double)...

Christian

As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet.

Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery.

Carlos Antollini25-Aug-01 5:05

25-Aug-01 5:05

I know that problem.
In DAO the engine supports the names with space but using this notacion [Field Name] but in ADO I saw that this don't work. Is for this that Always I use the name of the Fields without spaces. If is necesary I prefer to use Under score => _

Cheers!!!!
Wink | ;)

Carlos Antollini.

Ben Burnett24-Aug-01 17:39

24-Aug-01 17:39

>>>
CComBSTR bstrPath;
(*it)->get_FilePath(&bstrPath);
char * pStr = new char[bstrPath.Length() + 20];
memset(pStr, 0, bstrPath.Length() + 20);

sprintf(pStr, "FilePath = '%s'", (_bstr_t)bstrPath);

MessageBox(NULL, pStr, "", 0);
<<<

try this;

sprintf(pStr, "FilePath = '%s'", (char*)(_bstr_t)bstrPath);

Ben Burnett

---------
On the topic of code with no error handling -- It's not poor coding, it's "optimistic" Wink | ;)

Christian Graus24-Aug-01 17:51

24-Aug-01 17:51

Thanks - that works, but this line:

records->Filter = (_bstr_t)pStr;

still crashes. The string works if I pass it in manually or through a seperate _bstr_t. Creating a _bstr_t from pStr does not help.

Christian

As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet.

Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery.

Ben Burnett24-Aug-01 18:15

24-Aug-01 18:15

What is 'records', or actually beter yet, what does type is 'Filter'.

Ben Burnett

---------
On the topic of code with no error handling -- It's not poor coding, it's "optimistic" Wink | ;)

Christian Graus24-Aug-01 18:21

24-Aug-01 18:21

Records is a _RecordsetPtr. I am in ATL, no MFC support. The filter method of the Recordset works perfectly if I pass in the same string, but hard coded or created as a _bstr_t from a hardcoded value. The program crashes if I try it with the variable, if I use try/catch I get a meaningless error.

Christian

As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet.

Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery.

Michael Dunn24-Aug-01 18:20

Michael Dunn

24-Aug-01 18:20

That line crashes because (_bstr_t)pStr creates a temporary _bstr_t object which then gets deleted right away. That leaves records->Filter pointing at invalid memory. (This assumes records->Filter is a BSTR or other pointer type.)

--Mike--
http://home.inreach.com/mdunn/
A recent survey reports that 1/4 of all internet users in England surf for porn.
The other 3/4 just didn't want to admit it.

Christian Graus24-Aug-01 18:26

24-Aug-01 18:26

It's a _variant_t, but even if I create the _bstr_t seperately, it still crashes. I am certain it crashes because ADO does not recognise the command as valid, even though the syntax is the same when I pass in a hard coded value and it works.

_bstr_t s = pStr;
records->Filter = s;

Crashes

_bstr_t s = "FilePath = 'f:\\bibloi1.mdb'";
records->Filter = s;

works, even though the string I bring up in a MessageBox ( pStr) is exactly the same.

Christian

As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet.

Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery.

Ben Burnett24-Aug-01 18:38

24-Aug-01 18:38

I'm guessing you've already tried this, but maybe a little sanity check is in order;

_bstr_t s = pStr;
_bstr_t s2 = "FilePath = 'f:\\bibloi1.mdb'"; // or what ever pStr is supposed to be
if ( s == s2 ) {
    MessageBox ( "They are the same!!!");
}

Ben Burnett

---------
On the topic of code with no error handling -- It's not poor coding, it's "optimistic" Wink | ;)

Christian Graus24-Aug-01 20:03

24-Aug-01 20:03

Tim Deveaux25-Aug-01 14:54

Tim Deveaux

25-Aug-01 14:54

You have probably already figured this out, but if your DB allows spaces in field names (e.g. Access) most impls I've seen (i.e. Access) want you to surround them with [] brackets.

Careful though - SQL Server (which doesn't allow spaces, AFIK) will err out on you if you try to add the [].

It may be almost a rule of thumb that if you retrieve a field or table name that has an 0x20 in it you should slap the []s on 'em, and let 'em go otherwise.