Re: DateAdd equivalent? - C / C++ / MFC Discussion Boards

Re: DateAdd equivalent?

David Crow4-Feb-07 17:22

David Crow

4-Feb-07 17:22

If you are using MFC, see the COleDateTime class.

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

"Judge not by the eye but by the heart." - Native American Proverb

Re: DateAdd equivalent?

nm_1144-Feb-07 17:44

nm_114

4-Feb-07 17:44

DavidCrow wrote:
If you are using MFC, see the COleDateTime class.

Nope, pure Win32 Frown | :(

Re: DateAdd equivalent?

David Crow5-Feb-07 4:56

David Crow

5-Feb-07 4:56

Ok. How are you obtaining the date value you want to manipulate?

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

"Judge not by the eye but by the heart." - Native American Proverb

Re: DateAdd equivalent?

nm_1145-Feb-07 13:43

nm_114

5-Feb-07 13:43

GetSystemTime() (then converting it to local time).

Re: DateAdd equivalent?

David Crow6-Feb-07 3:10

David Crow

6-Feb-07 3:10

So do you have a SYSTEMTIME or a FILETIME object at this point?

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

"Judge not by the eye but by the heart." - Native American Proverb

Re: DateAdd equivalent?

nm_1146-Feb-07 11:58

nm_114

6-Feb-07 11:58

SYSTEMTIME.

SYSTEMTIME stDateIWantToAddDaysOrMonthsTo;
FILETIME ft, ftLocal;
GetSystemTimeAsFileTime(&ft);
FileTimeToLocalFileTime(&ft, &ftLocal);
FileTimeToSystemTime(&ftLocal, &stDateIWantToAddDaysOrMonthsTo);

Re: DateAdd equivalent?

David Crow6-Feb-07 15:18

David Crow

6-Feb-07 15:18

Ok, so what problem(s) are you having with "add or subtract any amount of hours, days, months etc. to a date?"

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

"Judge not by the eye but by the heart." - Native American Proverb

Re: DateAdd equivalent?

nm_1146-Feb-07 15:59

nm_114

6-Feb-07 15:59

I don't know of any function that does this. I was looking for something like VBScript's DateAdd where I could do something like DateAdd(Month, 24, &stMyDate) and it would add 24 months to the date (2 years), taking into account leap years etc..

Re: DateAdd equivalent?

David Crow6-Feb-07 16:09

David Crow

6-Feb-07 16:09

nm_114 wrote:
I don't know of any function that does this.

Why would you need a function, when one statement will work:

stDateIWantToAddDaysOrMonthsTo.wYear += 2;

You could roll your own function to this I suppose. Take a stroll through the other date/time functions to see what is available to you.

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

"Judge not by the eye but by the heart." - Native American Proverb

Re: DateAdd equivalent?

nm_1146-Feb-07 16:35

nm_114

6-Feb-07 16:35

DavidCrow wrote:
Why would you need a function, when one statement will work:

It was a bad example I guess. It needs to be arbitrary. Like DateAdd(Month, 309, mydate), DateAdd(Day, -909, mydate) etc. I'm not sure if I'm explaining it right.

DavidCrow wrote:
Take a stroll through the other date/time functions to see what is available to you.

I did. I didn't see anything like DateAdd.

Re: DateAdd equivalent?

David Crow7-Feb-07 2:35

David Crow

7-Feb-07 2:35

If you convert the SYSTEMTIME structure to a FILETIME structure, you can add/subtract such values.

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

"Judge not by the eye but by the heart." - Native American Proverb

Re: DateAdd equivalent?

nm_1147-Feb-07 13:37

nm_114

7-Feb-07 13:37

How? I found an article at
http://www.codeproject.com/datetime/winapi_datetime_ops.asp[^]
but it doesn't work with months/years, and I have no idea if it works right with leap years etc.

Re: DateAdd equivalent?

David Crow7-Feb-07 16:44

David Crow

7-Feb-07 16:44

nm_114 wrote:
How?

By using SystemTimeToFileTime().

nm_114 wrote:
I found an article at
http://www.codeproject.com/datetime/winapi_datetime_ops.asp[^]

That article is exactly what you need.

nm_114 wrote:

but it doesn't work with months/years

That's because a month does not have a constant value (i.e., 28, 29, 30, or 31 days) like the other items do.

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

"Judge not by the eye but by the heart." - Native American Proverb

Re: DateAdd equivalent?

nm_1148-Feb-07 12:06

nm_114

8-Feb-07 12:06

DavidCrow wrote:
nm_114 wrote:
How?

By using SystemTimeToFileTime().

Well I knew that much! Big Grin | :-D

I was asking how you do the adding/subtracting...

DavidCrow wrote:
That article is exactly what you need.

Well not really, as it doesn't handle months/years.

DavidCrow wrote:
That's because a month does not have a constant value (i.e., 28, 29, 30, or 31 days) like the other items do.

I knew that too! Big Grin | :-D

But it's ok, I guess what I was looking for doesn't exist (a tested/bug-free exact replica of DateAdd() in C++). Oh well Sigh | :sigh:

.
Thanks anyway.

Re: DateAdd equivalent?

David Crow8-Feb-07 16:55

David Crow

8-Feb-07 16:55

nm_114 wrote:
Well not really, as it doesn't handle months/years.

I already showed you how to add months to the SYSTEMTIME object. You would add years in the same fashion. What you have to account for when adding months is to make sure to increment years accordingly. For example, if it's September and you want to add four months, you would use:

wMonth = (wMonth + 4) % 12; // which would produce 0, for January

But you would then have to add one to the year.

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

"Judge not by the eye but by the heart." - Native American Proverb

Re: DateAdd equivalent?

nm_1148-Feb-07 19:02

nm_114

8-Feb-07 19:02

Yep. I guess I was hesitant to write my own because I don't know how to account for leap years, but I guess it's not critical. I'll probably use that other article and write something similar to your example for months/years.
Thanks.

Re: DateAdd equivalent?

David Crow9-Feb-07 2:45

David Crow

9-Feb-07 2:45

nm_114 wrote:
...I don't know how to account for leap years...

Are you kidding? Leap year algorithms/functions are plentiful here at CP, or even Googling for them.

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

"Judge not by the eye but by the heart." - Native American Proverb

Re: DateAdd equivalent?

kasturi_haribabu4-Feb-07 20:51

kasturi_haribabu

4-Feb-07 20:51

See if it helps you ...

int nDay;
int nMonth;
int nYear;

struct tm *when;
time_t now, result;
time( &now );
when = localtime( &now );//conversion from UTC to system time
if(when == NULL)//Error in the calculation of time
return -1;

when->tm_mday = when->tm_mday + nDays;
result = mktime( when );
if(result == (time_t)-1)//size of time_t = 0;result=-1--->error in calculation of result
{
return -1;
}
else
{
nDay = when->tm_mday;
nMonth = when->tm_mon+1;
nYear = when->tm_year+1900;
}

impossible to understand

cout and Persistent Formatting

Jeffrey Walton4-Feb-07 12:10

Jeffrey Walton

4-Feb-07 12:10

Hi All,

I'm prototyping code, and can't seem to persist a hexadecimal base. The following does not perform as expected (it still outputs base 10):

std::cout.unsetf ( std::ios_base::dec );<br />
std::cout.setf ( std::ios_base::hex );<br />
std::cout.setf ( std::ios_base::uppercase );

The alternative (which I am now trying to avoid) is:

std::cout << std::hex << 0x1000 << std::endl;

Any ideas? I'm not sure if I am not using the stream correctly, missing a Microsoft feature, or making an incorrect assumption for flag manipulation.

Thanks,
Jeff

Re: cout and Persistent Formatting [modified]

Mark Salsbery4-Feb-07 12:49

Mark Salsbery

4-Feb-07 12:49

So out of morbid curiosity I thought I'd like to see this in action. Smile | :)

Borrowing from example code:

// This works
  
   using namespace std;
 
   int i = 10;
 
   cout << i << endl;
 
   cout.unsetf( ios_base::dec );
   cout.setf( ios_base::hex | ios_base::uppercase );
   cout << i << endl;
 
   cout.setf( ios_base::dec );
   cout << i << endl;
 
   cout.setf( ios_base::hex, ios_base::dec | ios_base::uppercase );
   cout << i << endl;
 
Output:
10
A
10
a

// This does not work ...  WTF?
  
   using namespace std;
 
   int i = 10;
 
   cout << i << endl;
 
   cout.setf( ios_base::hex | ios_base::uppercase, ios_base::dec );
   cout << i << endl;
 
   cout.setf( ios_base::dec );
   cout << i << endl;
 
   cout.setf( ios_base::hex, ios_base::dec | ios_base::uppercase );
   cout << i << endl;
 
Output:
10
10
10
10

*EDIT* And, in the "working" example, why on the 3rd cout does the hex flag not nead to be unset.<br />
In fact doing so causes it to fail

-- modified at 19:03 Sunday 4th February, 2007

Re: cout and Persistent Formatting

Jeffrey Walton4-Feb-07 13:49

Jeffrey Walton

4-Feb-07 13:49

Hi Mark,

Thanks. It appears it should fall into the 'Microsoft Features' category... I still like to presume it is me (in the past, it usually is me).

Jeff

Urgent help:Minimize dialog,control disappears

Lewis Liu L4-Feb-07 10:16

Lewis Liu L

4-Feb-07 10:16

Hi
I made an MDI application, created a dialog, that dialog has several controls on it;when I call DoModal,all controls on it appear fine, but when I minimize the dialog, then restore it, all controls disappears, what am I doing wrong?

Re: Urgent help:Minimize dialog,control disappears

Hamid_RT5-Feb-07 7:02

Hamid_RT

5-Feb-07 7:02

Do you have any paint on your code?

WhiteSky

Re: Urgent help:Minimize dialog,control disappears

ThatsAlok6-Feb-07 20:16

ThatsAlok

6-Feb-07 20:16

LLewisLiu wrote:
made an MDI application, created a dialog, that dialog has several controls on it;when I call DoModal,all controls on it appear fine, but when I minimize the dialog, then restore it, all controls disappears, what am I doing wrong?

are you creating control dynamically???

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

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Alok Gupta
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sending input to window

dene999704-Feb-07 7:35

dene99970

4-Feb-07 7:35

I've attached to another window's input by calling AttachThreadInput(). I'm now trying to send text, as follows:

int size = strlen(text);
for(int i=0; i

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