I want to convert the current time into a string to later display it using the Drawtext function in WM_PAINT. Format hh:mm:ss.
And what is the most convenient way of getting the time to later turn it into a string.
There are many ways to format a time string.
If you want a specific format you can format the string yourself:
WCHAR buf[100];
SYSTEMTIME st;
GetLocalTime(&st); // Local time
wsprintfW(buf, L"%.2u:%.2u:%.2u", st.wHour, st.wMinute, st.wSecond); // 24h format
DrawTextW(hDC, buf, -1, &yourRect, DT_LEFT);
If you want to format the time using the users preferences then you must call GetTimeFormat instead. Or you could use the C standard library functions.
When you get a WM_PAINT message you call BeginPaint and GetClientRect, then DrawText and finally EndPaint.
Related
I'm trying to populate a Listbox using c++ on Visual Studio. I have an array of std:string and i want to use them. My solution doesn't seem to work:
std::string label = "something";
char *buffer;
buffer = _strdup((label).c_str());
I checked and the buffer variable contains the correct string, but then i call SendMessage
SendMessage(hwndList, LB_ADDSTRING, 0, (LPARAM)buffer);
The ListBox gets populated, but instead of "something" i see some random japanese characters...
SendMessage is a macro and it may be defined to SendMessageW, which uses Unicode string.
You are using std::string and char, so try using SendMessageA, which uses ANSI strings, explicitly.
I am using the following code for setting the time in a Date Control in MFC using C++
CTime date;
date = date.GetCurrentTime();
this->m_headerDate.SetTime(&date);
This will get the Date and set it to the control in what ever format the user machine uses. But I want to set it to a format of ONLY mm/dd/yyyy.
There should be some way of doing this in MFC. Are there any utility functions for this?
Thanks,
Without MFC:
#include <iostream>
#include <ctime>
using namespace std;
int main() {
const int MAXLEN = 80;
char s[MAXLEN];
time_t t = time(0);
strftime(s, MAXLEN, "%m/%d/%Y", localtime(&t));
std::cout << s << '\n';
}
Compiled Code
With MFC:
This function formats a date as a date string for a specified locale. The function formats either a specified date or the local system date.
int GetDateFormat(
LCID Locale,
DWORD dwFlags,
CONST SYSTEMTIME* lpDate,
LPCTSTR lpFormat,
LPTSTR lpDateStr,
int cchDate
);
change LPCTSTR lpFormat to MM:dd:yyyy
If you're talking about getting a specific textual representation of a date/time, you can use strftime() to format a date in many different ways, including the one specified in your question.
You will need a variable of type time_t using the facilities in the ctime header. So you can either switch to using those times, or I believe CTime::GetTime( ) will give you one.
However, if you're talking about forcing a control to display it's date/time in a specific format, that's a property of the control itself. For example, CDateTimeCtrl provides a SetFormat() method which will modify how it displays its data.
Here I'm storing value in a CString variable
Try this code:
CString strTime;
CTime date;
date = GetCurrentTime();
strTime = date.Format(_T("%m/%d/%Y"));
I have found a way of doing this...not sure if this is the simplest way though
Since we already have a datetime control .All we can do is just use the Setformat Function of the DatetimeControl. PFB an example of this
CDateTimeCtrl m_DateTimeCtrl;
m_DateTimeCtrl.SetFormat(_T("MM/dd/yyyy"));
The above will set it up to the format of 01/14/2015 which is desired. Thanks to Paxdiablo, Himanshu and Irrational Person for the inputs. They did point me in right direction with different options.
I am facing a problem on the WriteFile(); function using Win32 C++ Application. the second argument asks for a pointer to the buffer that is storing the information. what Syntax do I use to point the input text from the boxes? My information is text from the input of text boxes. What syntax do i use to create a pointer to that?
Here is a snippet of code the code I am using:
case IDC_BUTTON_ONE:
{
HANDLE hFile = CreateFile("C:\\test.txt", GENERIC_READ,
0, NULL, CREATE_NEW, FILE_FLAG_OVERLAPPED, NULL);
}
To write a control's text to a file you'll also need these lines:
char TextBuffer[256]; // Ascii
GetDlgItemTextA(hDlg, IDC_YOUR_CONTROL_ID, TextBuffer, ARRAY_SIZE(TextBuffer));
WriteFile(hFile, TextBuffer, strlen(TextBuffer), &SizeOut, lpOverlapped);
That'll just write plain old ASCII. If you want to use unicode and TCHARs (instead of chars) then you'll need to choose your encoding and write more than "just the bytes" from the text buffer.
After successfully solve this problem how to print a format string into window, another problem comes to me.
If there are many format strings, how to print them into window? For example below:
sprintf(buf, formatString-1...);
SendMessage(hwnd, WM_SETTEXT, NULL, (LPARAM)buf);
...
sprintf(buf, formatString-2...);
SendMessage(hwnd, WM_SETTEXT, NULL, (LPARAM)buf);
...
sprintf(buf, formatString-3...);
SendMessage(hwnd, WM_SETTEXT, NULL, (LPARAM)buf);
...
Notice that only formatString-3 is printed into window, while i want to put them all into window. How to do this?(PS: Please Do not use buf concatenate) Thank you!~
Are you trying to produce a console-style or log-style window, with multiple lines of text, one after the other?
If so, simplest approach is to pick a control that will do this for you. Something like a static (usually used for labels) typically is only useful for one string at a time. If you want to display more than one line of output, your two main options are:
Listbox control: add items to the end using LB_ADDSTRING. (You may want to follow that with LB_SETCURSEL or similar to select the last item, so that as items are added to the end, it will scroll to show the last item.)
Read-only Multi-line Edit control: append text to the end using the technique outlined here on MSDN. Note that with this approach, you need to supply the "\r\n" yourself to create a new line.
Each WM_SETTEXT message overwrites the previous one. That's why you only observe the effects of the final message.
Although you state that you don't want to concatenate the buffer before sending the WM_SETTEXT message, that's the only option with WM_SETTEXT.
If you have an edit control then you can insert text using the EM_REPLACESEL message.
I have inherited some MFC C++ code (it's an ActiveX OCX control running on a Windows Mobile 6.5 device) and I need to acquire the system date and time and append it as part of an existing string which gets passed via the com port to another device.
I can get the system date and time, but I can not figure out how to convert that into a string so that I can append it (via strcat.)
I've found a number of different answers on Google and Bing for what at first glance seemed like such a simple problem... :( but I don't know enough MFC C++ to adapt any of it to my needs. Any help would be greatly appreciated.
CTime t = CTime::GetCurrentTime();
CString s = t.Format( "%A, %B %d, %Y" );
char * str = (LPCTSTR) s;
Note, I believe that str is only valid while s is in scope. Probably should copy it off somewhere if you need it to be around after s is destroyed. If you are passing it to strcat() you're probably OK.
In MFC the following code is for current date in MMDDYYYY format.
CTime t = CTime::GetCurrentTime();
CString strDate = t.Format("%m%d%Y");