C++ Builder 参考手册 ➙ System::Dateutils ➙ StartOfTheMonth
这个日期时间所在月的开始时间，这个月的第一天 00:00:00.000
头文件：#include <System.DateUtils.hpp>
命名空间：System::Dateutils
函数原型：
System::TDateTime __fastcall StartOfTheMonth(const System::TDateTime AValue);
参数：
- AValue：日期时间；
返回值：
- 这个日期时间所在月的开始时间，这个月的第一天 00:00:00.000。
例：
#include <System.DateUtils.hpp>
void __fastcall TForm1::Button1Click(TObject *Sender)
{
TDateTime dt = Sysutils::Now();
Memo1->Lines->Add(FormatDateTime(L"yyyy/mm/dd hh:nn:ss.zzz", dt));
Memo1->Lines->Add(FormatDateTime(L"yyyy/mm/dd hh:nn:ss.zzz", StartOfTheMonth(dt)));
Memo1->Lines->Add(FormatDateTime(L"yyyy/mm/dd hh:nn:ss.zzz", EndOfTheMonth(dt)));
}
运行结果：
相关：
- System::Dateutils::StartOfTheYear
- System::Dateutils::EndOfTheYear
- System::Dateutils::StartOfTheMonth
- System::Dateutils::EndOfTheMonth
- System::Dateutils::StartOfTheWeek
- System::Dateutils::EndOfTheWeek
- System::Dateutils::StartOfTheDay
- System::Dateutils::EndOfTheDay
- System::Dateutils::StartOfAYear
- System::Dateutils::EndOfAYear
- System::Dateutils::StartOfAMonth
- System::Dateutils::EndOfAMonth
- System::Dateutils::StartOfAWeek
- System::Dateutils::EndOfAWeek
- System::Dateutils::StartOfADay
- System::Dateutils::EndOfADay
- System::Dateutils::StartOfADay
- System::Dateutils::EndOfADay
- System::Dateutils::DaysInYear
- System::Dateutils::DaysInAYear
- System::Dateutils::DaysInMonth
- System::Dateutils::DaysInAMonth
- System::Dateutils::WeeksInYear
- System::Dateutils::WeeksInAYear
- System::Dateutils
C++ Builder 参考手册 ➙ System::Dateutils ➙ StartOfTheMonth
