Month Calendar : output selected range to MessageBox - pls explain

Hello,

I have created a Month Calendar Control and have enabled MCS_MULTISELECT.

I am trying to implement the MonthCal_GetSelRange() macro to capture a selected range in the Calendar Control. So far my switch looks like this:

Code:

---

case IDC_BTN_MOON:
                {
                    SYSTEMTIME rng[2];

                    MonthCal_GetSelRange(hWndMonthCal, &rng);


                }

---

How do I get that range to display in a MessageBox?

Code:

---

MessageBox(hwndDlg, ??, 0);

---

I have tried passing SYSTEMTIME WORDs ( rng.wDayOfWeek) but I simply cant get it right. I know it is likely that such usage is no good, but I am trying...

I have been using the Method approach to creating the Month Calendar and other controls.

You must first format SYSTEMTIME values to text (character array) and then pass in this array to MessageBox.
You can use GetTimeFormat to format SYSTEMTIME to text.

Quote:

---

Originally Posted by VictorN

You must first format SYSTEMTIME values to text (character array) and then pass in this array to MessageBox.
You can use GetTimeFormat to format SYSTEMTIME to text.

---

Code:

---

SYSTEMTIME* rng[2];
                   
MonthCal_GetSelRange(hWndMonthCal, rng);

GetTimeFormat(LOCALE_SYSTEM_DEFAULT, TIME_NOMINUTESORSECONDS, rng, ?, 30);

---

Thanks Victor, but could you please elaborate? I don't know how to declare a buffer pointer "?". The other parameters should be ok, but I am not sure about how to use the GetTimeFormat function either.

http://www.google.com/search?sourcei...htsa=1&qscrl=1

Is there a method of conversion that will include the Date - which for my purpose is more important than the Time? GetTimeFormat does not recognise dates.

By the way, here is the function with parameters I chose:

Code:

---

GetTimeFormat(NULL, TIME_NOMINUTESORSECONDS, rng, NULL, NULL, 0);

---

Quote:

---

Originally Posted by Morbane

Is there a method of conversion that will include the Date - which for my purpose is more important than the Time? GetTimeFormat does not recognise dates.

---

Ahh, sorry!
It should have been GetDateFormat API!

Cool.

But the GetDateFormat() returns an int. I can't seem to figure out how it converts to char* (or c_str() ).

Moreover, MonthCal_GetSelRange() returns a BOOL. How is that supposed to reveal a range of two dates?

Quote:

---

Originally Posted by Morbane

But the GetDateFormat() returns an int.

---

But the GetDateFormat() has a parameter LPTSTR lpDateStr.

According to http://msdn.microsoft.com/en-us/libr...8VS.85%29.aspx the int returned simply tells you the number of chars written to the buffer that the result is stored in. ie the fifth argument that you pass to the function. so that's where you wanna be looking for the formatted date...

edit: oops beat me to it ovidiucucu

Quote:

---

Originally Posted by Morbane

Moreover, MonthCal_GetSelRange() returns a BOOL. How is that supposed to reveal a range of two dates?

---

Moreover, MonthCal_GetSelRange has a parameter LPSYSTEMTIME lprgSysTimeArray.

Quote:

---

Originally Posted by Morbane

But the GetDateFormat() returns an int. I can't seem to figure out how it converts to char* (or c_str() ).

---

getdateformat c++ example

Quote:

---

Originally Posted by Morbane

Moreover, MonthCal_GetSelRange() returns a BOOL. How is that supposed to reveal a range of two dates?

---

PLease, look at your OP:

Code:

---

case IDC_BTN_MOON:
                {
                    SYSTEMTIME rng[2];

                    MonthCal_GetSelRange(hWndMonthCal, &rng);
                }

---

how do you think, why are you passing SYSTEMTIME array in this macro?
And, BTW, your code contains a bug. There must be

Code:

---

MonthCal_GetSelRange(hWndMonthCal, rng);

---

OK! Thanks Cheezewizz and ovidiucucu - very much - it makes so much sense now. The descriptions on the msdn pages state (in) or (out) for any given parameter. Now I know why ;)

Also Thanks to you VictorN!

All you guys are very helpful - and patient.

Here is the working switch:

Code:

---

case IDC_BTN_MOON:
                {
                    SYSTEMTIME rng[2];

                    char buf[50];

                    MonthCal_GetSelRange(hWndMonthCal, rng); //BOOL

                    GetDateFormat(NULL, DATE_SHORTDATE, rng, NULL, buf, 50); //int


                    MessageBox(hwndDlg, buf, "Current Date", 0);
                }

---

Next, I am trying to output the range captured by MonthCal_GetSelRange

For MonthCal_GetSelRange(), shouldn't the rng variable have stored an actual date range?

The code in my previous post only seems to result in the current date even though the rng variable is passed into GetDateFormat() - the buf variable doesn't seem to hold the full string.

What am I doing wrong?

There must be a way to specify the elements of the rng array so that they can be passed into GetDateFormat, either separately or together, but I m having trouble finding a reference for this scenario.

Advice is humbly requested.

No, GetDateFormat works only with a single SYSTEMTIME instance, not with an array.
You should either format two different substrings and then concatenate them or use sprintf and pass in all needed members of both SYSTEMTIME instances (with all are WORD or "unsigned short")

Then what is the MonthCal_GetSelRange() for? Shouldn't there be a way to pass it's contents, of the 2 element array of SYSTEMTIME structures?? Or at least handle them for processing in some way?

Quote:

---

Originally Posted by Morbane

Then what is the MonthCal_GetSelRange() for? Shouldn't there be a way to pass it's contents, of the 2 element array of SYSTEMTIME structures?? Or at least handle them for processing in some way?

---

Didn't you read the MSDN about MonthCal_GetSelRange? :confused:

Quote:

---

MonthCal_GetSelRange


Retrieves date information that represents the upper and lower limits of the date range currently selected by the user. You can use this macro or send the MCM_GETSELRANGE message explicitly.

---

And it's up to you where and how to use the returned SYSTEMTIME array with these "upper and lower limits of the date range currently selected by the user".

Ok...
I have managed to isolate the lower and upper ranges of MonthCal_GetSelRange(), thus:

Code:

---

SYSTEMTIME rng[2];

                    MonthCal_GetSelRange(hWndMonthCal, rng);
                    SYSTEMTIME low = rng[0];
                    SYSTEMTIME high = rng[1];

                    char buf1[30];
                    GetDateFormat(NULL, DATE_LONGDATE, &low, NULL, buf1, 30);
                    char buf2[30];
                    GetDateFormat(NULL, DATE_LONGDATE, &high, NULL, buf2, 30);

                    MessageBox(hwndDlg, buf, "Current Date", 0);

---

How do I get buf1 and buf2 into the MessageBox as a single unit with a pretty "to" in between?

1. Why not just pass in the rng[0], rng[1]? Example:

Code:

---

    char buf1[30];
    GetDateFormat(NULL, DATE_LONGDATE, &rng[0, NULL, buf1, 30);

---

2.

Code:

---

char buf[100];
strcpy(buf, buf1);
strcat(buf, " to ");
strcat(buf, buf2);
MessageBox(hwndDlg, buf, "Current Date", 0);

---

Very NICE indeed.

I looked at strcat and the example in cplusplus.com/reference, but I hesitated, I wasn't sure about how it would work. It was exactly what I needed nevertheless.

Thanks again (and again :)

Just by the by, in my calendar, if someone were to only select 1 day - the output remains twofold, in such a case it says October 19, 2010 to October 19, 2010. Is there a way to prevent that duplication? I haven't explored that yet but I thought I would ask anyway.

So I tried this:

Code:

---

                    if(buf1 == buf2)
                    {
                        MessageBox(hwndDlg, buf1, "Current Date", 0);
                    }
                    else
                    {
                        MessageBox(hwndDlg, buf, "Current Range", 0);
                    }

---

But it doesn't work - the logic is messed up somehow.

Any suggestions?

Quote:

---

Originally Posted by Morbane

So I tried this:

Code:

---

                    if(buf1 == buf2)
 ...

---

But it doesn't work - the logic is messed up somehow.

---

Of course it doesn't!
Because you compare the values of two pointers which are absolutely different!
You have to compare SYSTEMTIME objects (rng[0] and rng[1] in your case)

When I try to use:

Code:

---

if(rng[0] == rng[1])
...

---

It says "there is no match for operator== for rng[0] == rng[1]"

I know about overloading operators - but I do not know how or if it necessary.

Or I am doing something wrong again.

Any suggestions?

Again, Thanks.

Ok, then compare each member of SYSTEMTIME that makes sense for you. Like:

Code:

---

SYSTEMTIME rng[2];
...
if(        rng[0].wYear == rng[1].wYear &&
        rng[0].wMonth == rng[1].wMonth &&
        rng[0].wDay == rng[1].wDay )
{
        MessageBox(hwndDlg, buf1, "Current Date", 0);
}
...

---

Victor, you are amazing.

I have experimented with the SYSTEMTIME members in various efforts to get this worked out, but at this point, it is quite late here and I don't think I would have thought of it on my own in this case.

Many thanks.

See you next time, no doubt I will be back for more insights.