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