// *********************************************************
// 文字列日付の経過日数
// 戻り値 : 経過日数( 失敗時は -1 )
// *********************************************************
int LboxString::DateDiff( LboxString *LDate )
{
	return LboxString::DateDiff( LDate->szLboxString );
}
int LboxString::DateDiff( LPTSTR lpDate )
{
	LboxString LString;
	LboxInfo Info;

	LString.operator = (lpDate);

	BOOL bRet;
	SYSTEMTIME st1;
	SYSTEMTIME st2;

	bRet = this->ToSystemTime( &st1 );
	if ( !bRet ) {
		return -1;
	}
	bRet = LString.ToSystemTime( &st2 );
	if ( !bRet ) {
		return -1;
	}

	return Info.DateDiff( &st1, &st2 );

}