#using <System.dll> #using <System.Windows.Forms.dll> using namespace System; using namespace System::Windows::Forms;

Transcription

1 Lecture #12 Handling date and time values Handling Date and Time Values In the.net Framework environment, the DateTime value type represents dates and times with values ranging from 12:00:00 midnight, January 1, 0001 Anno Domini (Common Era) through 11:59:59 P.M., December 31, 9999 A.D.. A DateTime value is always expressed in the context of an explicit or default calendar. Time values are measured in 100-nanosecond units called ticks, and a particular date is the number of ticks since 12:00 midnight, January 1, 0001 A.D. (C.E.) in the GregorianCalendar calendar. For example, a tick value of L represents the date, Friday, January 01, :00:00 midnight. Since the DateTime is a non-static member of the System class, it needs a value as reference to retrieve values. There are three reference value you can use: Now: Gets a DateTime object that is set to the current date and time on this computer, expressed as the local time. Today: Gets the current date. UtcNow: tells the date and time as it would be in Coordinated Universal Time, which is also called the Greenwich Mean Time time zone. To use them, you declare a variable as DateTime type, and reference the variable to either Now or Today. For example, DateTime dt = DateTime::Now; MessageBox::Show(Convert::ToString(dt)); A short-hand way is: DateTime dt = DateTime::Now; MessageBox::Show(dt+""); Alternatively, you can simply convert the referenced Now or Today value to a string. For example, Visual C++ Programming Penn Wu, PhD 321

2 MessageBox::Show(Convert::ToString(DateTime::Today)); Without using the Convert::ToString() method, you can simply concatenate the DateTime value with a NULL string. For example, MessageBox::Show(DateTime::Today + ""); By calling any of the overloads of the DateTime constructor that allow you to specify specific elements of the date and time value (such as the year, month, and day, or the number of ticks). The DateTime constructor can initialize a new instance of the DateTime structure based on a list of available forms. One form of the DateTime constructor support the following syntax to initialize a new instance of the DateTime structure to the specified year, month, and day. DateTime(year, month, day) For example, the following sets the date to May 1, DateTime dt = DateTime(2018, 5, 1); MessageBox::Show(dt + ""); The output looks: Another form is: DateTime(year, month, day, hour, minute, second) The following statement illustrates a call to one of the DateTime constructors to create a date with a specific year, month, day, hour, minute, and second. It sets the date and time to May 1, 2018, 8:30:52. Visual C++ Programming Penn Wu, PhD 322

3 DateTime dt = DateTime(2018, 5, 1, 8, 30, 52); MessageBox::Show(dt + ""); The output looks: By assigning the DateTime object a date and time value returned by a property or method. The following example assigns the current date and time, the current Coordinated Universal Time (UTC) date and time, and the current date to three new DateTime variables. DateTime dt1 = DateTime.Now; DateTime dt2 = DateTime.Today; DateTime dt3 = DateTime.UtcNow; Once the DateTime object (variable) has a reference valve, you can use the following commonly used properties to retrieve specific data: Date: Gets the date related values express as a string. DayOfWeek: Gets the day of the week expressed as a string value such as Sunday. Day: Gets the day of the month expressed as an integral value between 1 and 31. DayOfYear: Gets the day of the year expressed as an integral value between 1 and 366. Hour: Gets the hour value of the date expressed as an integral value between 0 and 23. Minute: Gets the minute value of the date expressed as an integral value between 0 and 59. Month: Gets the month value of the date expressed as an integral value between 1 and 12. Second: Gets the seconds value of the date expressed as an integral value between 0 and 59. Year: Gets the year value of the date expressed as an integral value between 1 and For example, String^ str; DateTime dt = DateTime::Today; str = Convert::ToString(dt.Date) + "\n" + Convert::ToString(dt.DayOfWeek) + "\n" + Convert::ToString(dt.Day) + "\n" + Convert::ToString(dt.DayOfYear) + "\n" + Convert::ToString(dt.Month) + "\n" + Convert::ToString(dt.Year) + "\n"; Visual C++ Programming Penn Wu, PhD 323

4 MessageBox::Show(str); You can take advantages of these properties by using them to create programs like Christmas countdown. For example, DateTime dt = DateTime::Now; DateTime xmas = DateTime(DateTime::Now.Year, 12, 25); if ((xmas.dayofyear - dt.dayofyear) < 0) MessageBox::Show("You missed the " + DateTime::Now.Year + " Christmas!"); else MessageBox::Show("Just " + (xmas.dayofyear - dt.dayofyear) + " day(s) to " + DateTime::Now.Year + " Christmas!"); A sample output looks: Commonly used methods are: ToLocalTime(): Converts the value of the current DateTime object to local time. ToLongDateString(): Converts the value of the current DateTime object to its equivalent long date string representation. ToLongTimeString(): Converts the value of the current DateTime object to its equivalent long time string representation. ToShortDateString(): Converts the value of the current DateTime object to its equivalent short date string representation. ToShortTimeString(): Converts the value of the current DateTime object to its equivalent short time string representation. ToUniversalTime(): Converts the value of the current DateTime object to Coordinated Universal Time (UTC). Notice that all these methods are meant to convert a given date/time value to different format, namely they must be given a value. In the following example, the dt variable (object) get the date/time value from the computer. Visual C++ Programming Penn Wu, PhD 324

5 String^ str = "Output formats:\n"; DateTime dt = DateTime::Now; str += "ToLocalTime: " + dt.tolocaltime() + "\n" + "ToLongDateString: " + dt.tolongdatestring() + "\n" + "ToLongTimeString: " + dt.tolongtimestring() + "\n" + "ToShortDateString: " + dt.toshortdatestring() + "\n" + "ToShortTimeString: " + dt.toshorttimestring() + "\n" + "ToUniversalTime: " + dt.touniversaltime() + "\n"; MessageBox::Show(str); A sample output looks: Another example, String^ str = Convert::ToString(DateTime::Now.ToLocalTime()); MessageBox::Show(str); The DataTime class can be used as a method that specifies a new DateTime value. The syntax is: DateTime(year,month,day,hour,minute,second,millisecond,Calendar ) where year, month, day, hour, minute, second, and millisecond are Int32 integers. Calendar is used for specifying calendar type. For example, to specify the DateTime value of the Christmas of the current year (given by DataTime::Now.Year), use: Visual C++ Programming Penn Wu, PhD 325

6 DateTime xmas = DateTime(Convert::ToInt32(DateTime::Now.Year),12,25,0,0,0); MessageBox::Show(xmas + ""); If you add the following to the namespace section, you can then use display the Christmas date in Chinese Calendar. DateTime cxmas = DateTime(Convert::ToInt32(DateTime::Now.Year),12,25); ChineseLunisolarCalendar^ ch = gcnew ChineseLunisolarCalendar; int d = ch->getdayofmonth(cxmas); // convert to Chinese value int m = ch->getmonth(cxmas); // convert to Chinese month int y = ch->getyear(cxmas); // convert to Chinese year cxmas = DateTime(y, m, d); MessageBox::Show(Convert::ToString(DateTime::Now.Year) + " Christmas is " + cxmas + " in Chinese calendar!"); A sample output looks: In one of the previous lecture, you had learned to write the code to return the Chinese Zodiac. The following is a much precise version. #include "InputBox.cpp" String^ str = InputBox::Show("Enter your birthdate [yyyy, mm, dd]: "); DateTime bd = DateTime(Convert::ToDateTime(str)); Visual C++ Programming Penn Wu, PhD 326

7 ChineseLunisolarCalendar^ ch = gcnew ChineseLunisolarCalendar; int d = ch->getdayofmonth(bd); // convert to Chinese value int m = ch->getmonth(bd); // convert to Chinese month int y = ch->getyear(bd); // convert to Chinese year bd = DateTime(y, m, d); String^ zd =""; switch (y%12) case 0: zd = "Monkey"; break; case 1: zd = "Rooster"; break; case 2: zd = "Dog"; break; case 3: zd = "Pig"; break; case 4: zd = "Rat"; break; case 5: zd = "Ox"; break; case 6: zd = "Tiger"; break; case 7: zd = "Rabbit"; break; case 8: zd = "Dragon"; break; case 9: zd = "Snake"; break; case 10: zd = "Horse"; break; case 11: zd = "Goat"; break; MessageBox::Show(bd + "\nyour were born in " + zd + " year in Chinese calendar!"); The other calendar types are: ChineseLunisolarCalendar EastAsianLunisolarCalendar GregorianCalendar HebrewCalendar HijriCalendar JulianCalendar PersianCalendar ThaiBuddhistCalendar UmAlQuraCalendar For example, DateTime cxmas = DateTime(Convert::ToInt32(DateTime::Now.Year),12,25); PersianCalendar^ ps = gcnew PersianCalendar; int d = ps->getdayofmonth(cxmas); // convert to Persian value int m = ps->getmonth(cxmas); // convert to Persian month int y = ps->getyear(cxmas); // convert to Persian year Visual C++ Programming Penn Wu, PhD 327

8 cxmas = DateTime(y, m, d); MessageBox::Show(Convert::ToString(DateTime::Now.Year) + " Christmas is " + cxmas + " in Persian calendar!"); A sample output looks: The DateTimePicke r class The.NET Framework provides a DateTimePicker class which provides a set of tools that allow the user to select a date and a time and to display the date and time with a specified format. The following creates a new DateTimePicker control and initialize it. DateTimePicker^ datetimepicker1 = gcnew DateTimePicker; The following is a simple code that creates a DateTimePicker object. #using <System.Drawing.dll> using namespace System::Drawing; public ref class Form1: public Form DateTimePicker^ datetimepicker1; //global public: Form1() datetimepicker1 = gcnew DateTimePicker; datetimepicker1->location = Point(10, 10); datetimepicker1->valuechanged += gcnew EventHandler(this, &Form1::dateTimePicker1_ValueChanged); Controls->Add(dateTimePicker1); private: Void datetimepicker1_valuechanged(object^ sender, EventArgs^ e) int d = Convert::ToInt16(dateTimePicker1->Value.Day); int m = Convert::ToInt16(dateTimePicker1->Value.Month); int y = Convert::ToInt16(dateTimePicker1->Value.Year); DateTime dt = DateTime(y, m, d); MessageBox::Show("The date you picked is " + dt); ; [STAThread] Visual C++ Programming Penn Wu, PhD 328

9 int main() Application::Run(gcnew Form1); A sample output looks: The ValueChanged event raises when the Value property changes. User input is validated before this event is raised; therefore, you can use this event to handle data and time value settings. The DateTimePicker class supports the Value property to set the date/time value based on the DateTime structure; therefore, you can use the following format to assign special DateTime values. and datetimepicker1->value.propertyname For example, Value.Day gets the day of the month represented by this instance. Value.Month gets the month component of the date represented by this instance. Value.Year gets the year component of the date represented by this instance. Value.Now gets a DateTime object that is set to the current date and time on this computer, expressed as the local time. The MaxDate property sets the maximum date and time that can be selected in the control. The MinDate property sets the minimum date and time that can be selected in the control. The following sets the MinDate and MaxDate. datetimepicker1->mindate = DateTime(2005, 12, 31); datetimepicker1->maxdate = DateTime::Today; The ShowCheckBox property is a Boolean property that sets whether a check box is displayed to the left of the selected date. The ShowUpDown sets whether a spin button control (also known as an up-down control) is used to adjust the date/time value. The following code can show the CheckBox and display the control as an up-down control. datetimepicker1->showcheckbox = true; datetimepicker1->showupdown = true; If you rather use a customized date format, you need to set the CustomFormat string. Visit for a list of directives that may be used to defined the date and time format. To display string literals that contain date and time separators or to format strings, you must use escape characters in the substring. For example, to display the date as June 15 at 12:00 PM, set the CustomFormat property to "MMMM dd 'at' t:mm tt". If the at substring is not enclosed by escape characters, the result is June 15 ap 12:00PM because the t character is read as the one-letter A.M./P.M. format string. The format strings can be combined to format the date and time. For example, to display the date and time as 06/15/ :00 PM, this property should be set to "MM'/'dd'/'yyyy hh':'mm tt". Visual C++ Programming Penn Wu, PhD 329

10 The Format property actually sets the format of the date and time displayed in the control. The Format property must be set to DateTimePickerFormat::Custom for the CustomFormat property to affect the formatting of the displayed date and time. The following statements set the CustomFormat string. datetimepicker1->customformat = "MMMM dd, yyyy - dddd"; datetimepicker1->format = DateTimePickerFormat::Custom; Handling time zone You can use the TimeZone class to retrieve information about the current time zone, and to convert times from local time to any time zone. The TimeZOne class is usually used as a Data type, with which you can define a variable (object) and use it to work with the methods and properties of the TimeZone class. Three properties are: CurrentTimeZone: Gets the time zone of the current computer. DaylightName: Gets the daylight saving time zone name. StandardName: Gets the standard time zone name. The following example retrieve your current time zone and the daylight saving time zone name TimeZone^ tz = TimeZone::CurrentTimeZone; MessageBox::Show("Your time zone: " + tz->standardname + "\n" + "Your daylight time zone: " + tz->daylightname); The output looks: Interestingly, Microsoft recommends the programmers to use the TimeZoneInfo class instead of the TimeZone class whenever possible. The TimeZoneInfo class represents any time zone in the world. It supports the following properties: BaseUtcOffset: Gets the time difference between the current time zone s standard time and Coordinated Universal Time (UTC). DaylightName: Gets the display name for the current time zone's daylight saving time. DisplayName: Gets the general display name that represents the time zone. Id: Gets the time zone identifier. Local: Gets a TimeZoneInfo object that represents the local time zone. StandardName: Gets the display name for the time zone's standard time. Visual C++ Programming Penn Wu, PhD 330

11 SupportsDaylightSavingTime: Gets a value indicating whether the time zone has any daylight saving time rules. Utc: Gets a TimeZoneInfo object that represents the Coordinated Universal Time (UTC) zone. The following illustrates how to use this class. TimeZoneInfo^ tz = TimeZoneInfo::Local; MessageBox::Show("Your time zone: " + tz->standardname + "\n" + "Your daylight time zone: " + tz->daylightname + "\n" + "General name: " + tz->displayname + "\n" + "Time zone ID: " + tz->id + "\n" + ); The output looks: Formatting date and time values The DateTimeFormatInfo class of the System.Globalization namespace defines how DateTime values are formatted and displayed, depending on the culture. This class contains information, such as date patterns, time patterns, and AM/PM designators. In practice, you need to add the following to the namespace section in order to use the designators, which are parameters representing pre-defined formats. Using namespace System::Globalization; Simply declare a variable (object) which represents a DateTime value, and then use the ToString() method with designator in it to specify the format. For example, to use the F designator: Visual C++ Programming Penn Wu, PhD 331

12 The output is: String^ str = "Date time formats:\n\n"; DateTime bt = DateTime(2025,11,30, 12,29,37); str += bt.tostring("d") + "\n" + bt.tostring("d") + "\n" + bt.tostring("f") + "\n" + bt.tostring("f") + "\n" + bt.tostring("g") + "\n" + bt.tostring("g") + "\n" + bt.tostring("t") + "\n" + bt.tostring("t") + "\n" + bt.tostring("u") + "\n" + bt.tostring("u") + "\n"; MessageBox::Show(str); Commonly used designators are: designator Description d ShortDatePattern D LongDatePattern f Full date and time (long date and short time) F FullDateTimePattern (long date and long time) g General (short date and short time) G General (short date and long time) m or M MonthDayPattern t ShortTimePattern T LongTimePattern u Universal Sortable DateTime Pattern. Using the format for universal time display; with this format pattern, the formatting or parsing operation always uses the invariant culture U Full date and time (long date and long time) using universal time y or Y YearMonthPattern All the above designators represent pre-defined format, and you cannot customize the formats. If there is a need to customize the format, you will need to refer to the table in which lists the custom DateTime format patterns and their behavior. For example, given a customized date and time format, Visual C++ Programming Penn Wu, PhD 332

13 String^ str = DateTime::Now.ToString("dd MMM, yyyy... HH-mm-ss tt"); MessageBox::Show(str); A sample output looks: Handling Daylight saving time Daylight saving time is a period during the year when the time is advanced, usually by an hour, to take advantage of the extended daylight hours. There is a DaylightTime class of the System::Globalization class. You can use it to define the period of daylight saving time. At the end of the period, the time is set back to the standard time. Be sure to add the following line to the namespace section in order to use this class. Using namespace System::Globalization; Usually DaylightTime is used as a method. The syntax is: DaylightTime(Start, End, Delta) Parameters are: Start: The DateTime that represents the date and time when the daylight saving period begins. The value must be in local time. End: The DateTime that represents the date and time when the daylight saving period ends. The value must be in local time. Delta: The TimeSpan that represents the difference between the standard time and the daylight saving time in ticks. For example, assuming President Robots in 2050 announced that the starting and ending dates of daylight saving time for 2051 is Feb 12 and Dec 10, You can use the following code to redefine the daylight saving time period for the year (Note: It is supposed be between Mar 12 ~ Nov 5, 2051) DaylightTime^ dt = gcnew DaylightTime(DateTime(2051,2,11), DateTime(2051,12,10), TimeSpan(2,0,0)); Visual C++ Programming Penn Wu, PhD 333

14 The above code uses the TimeSpan structure with the following syntax to initialize a new instance of the TimeSpan structure to a specified number of hours, minutes, and seconds. TimeSpan(hours, minutes, seconds) A TimeSpan object represents a time interval (duration of time or elapsed time) that is measured as a positive or negative number of days, hours, minutes, seconds, and fractions of a second. The TimeSpan structure can also be used to represent the time of day, but only if the time is unrelated to a particular date. These three parameters, Start, End, and Delta, of the DaylightTime object are also used as properties. For example, TimeZone^ tz = TimeZone::CurrentTimeZone; DaylightTime^ dt = tz- >GetDaylightChanges( DateTime::Now.Year ); String^ str = "In " + DateTime::Now.Year + ", the dayling saving time\n" + "\tstarts on : " + dt->start + "\n" + "\tends on : " + dt->end +"\n" + "\tdifference : " + dt->delta ; MessageBox::Show(str); The GetDaylightChanges() method returns the daylight saving time period for a particular year. A sample output looks: The IsDaylightSavingTime() method returns a value indicating whether the specified date and time is within a daylight saving time period. For example, the following returns a Boolean value (either True or False). Visual C++ Programming Penn Wu, PhD 334

15 int main() TimeZone^ tz = TimeZone::CurrentTimeZone; MessageBox::Show(tz->IsDaylightSavingTime(DateTime::Now)+""); Designing a simple world clock Many of the tools introduced in this lecture are useful in handling date and time. One example is to create a simple world clock with calendar. The DateTime structure helps to retrieve the current local date and time values as well as those of UTC. The following creates two DateTime objects, dt and ut, for holding the current date and time values of local and UTC time zone. DateTime dt = DateTime::Now; // current local time DateTime ut = DateTime::UtcNow; // current UTC date time The instructor chooses the G directive to display the date and time values in the format of short date and long time (e.g. 9/14/2019 5:27:56 PM). MessageBox::Show(dt.ToString("G") + ""); The TimeZoneInfo structure helps to retrieve information of the local time zone. The DisplayName property returns the name of the local time zone. TimeZoneInfo^ tz = TimeZoneInfo::Local; MessageBox::Show(tz->DisplayName + ""); The TimeSpan structure can contribute to the calculation of time difference across time zones. It is necessary to know that London, UK is in a time zone that has a +1 hour offset against the UTC time zone. ut = DateTime::UtcNow; // current UTC date time DateTime ld = ut + TimeSpan(1, 0, 0); // offset: +1 hour The following is a sample code that displays local (wherever the user is), UTC, and London date and time values in a Windows Form application. By the way, the instructor chooses to display these values by Label controls. #using <System.Drawing.dll> using namespace System::Drawing; public ref class Form1: public Form Label^ local; Label^ utc; Label^ London; DateTime dt; DateTime ut; //UTC date time DateTime ld; //London date time Visual C++ Programming Penn Wu, PhD 335

16 public: Form1() this->size = Drawing::Size(300, 400); TimeZoneInfo^ tz = TimeZoneInfo::Local; dt = DateTime::Now; // current local time local = gcnew Label; local->text = "Local: " + dt.tostring("g") + "\n" + tz- >DisplayName; local->autosize = true; local->location = Point(10, 10); Controls->Add(local); ut = DateTime::UtcNow; // current UTC date time utc = gcnew Label; utc->text = "UTC: " + ut.tostring("g"); utc->autosize = true; utc->location = Point(10, 110); Controls->Add(utc); ld = ut + TimeSpan(1, 0, 0); // London and UTC time zone offset: +1 hour ; London = gcnew Label; London->Text = "London: " + ld.tostring("g"); London->AutoSize = true; London->Location = Point(10, 210); Controls->Add(London); [STAThread] int main() Application::Run(gcnew Form1); The above code only displays the date and time values once. It cannot update the contents. To turn it into a clock, there is a need to add a Timer component with a Tick event to update the date and time value every second. The following creates a Timer component named timer1, sets its Interval to 1000 milliseconds (which equals to 1 second), ties timer1 with a Tick event, associates the Tick event with an event handler named timer1_tick, and starts the timer. Timer^ timer1 = gcnew Timer; timer1->tick += gcnew EventHandler(this, &Form1::timer1_Tick); timer1->interval = 1000; timer1->start(); The event handler is responsible for updating the date and time values of every time zones. The following is the sample code. private: System::Void timer1_tick(object^ sender, EventArgs^ e) tz = TimeZoneInfo::Local; dt = DateTime::Now; // current local time local->text = "Local: " + dt.tostring("g") + "\n" + tz- >DisplayName; Visual C++ Programming Penn Wu, PhD 336

17 ut = DateTime::UtcNow; // current UTC date time utc->text = "UTC: " + ut.tostring("g"); ld = ut + TimeSpan(1, 0, 0); // London-UTC time zone offset: +1 hour London->Text = "London: " + ld.tostring("g"); Review Questions 1. In Visual Studio, the Time values are measured in. A. 10-milliseconds B. 100-milliseconds C. 10-nanoseconds D. 100-nanoseconds 2. Given the following code, which statement is correct? DateTime dt = DateTime(6, 5, 7, 8, 9, 10); A. The year value is B. The month value is 7. C. The minute value is 9. D. The minute value is Which statement can specify the DateTime value of the Christmas of the current year? A. DateTime xmas = DateTime(Now.Year,12,25,0,0,0); B. DateTime xmas = DateTime(DateTime::Now.Year,12,25,0,0,0); C. DateTime xmas = DateTime(Convert::ToInt32(Now.Year),12,25,0,0,0); D. DateTime xmas = DateTime(Convert::ToInt32(DateTime::Now.Year),12,25,0,0,0); 4. Which assigns the current Coordinated Universal Time (UTC) date and time? A. DateTime dt1 = DateTime.Now; B. DateTime dt2 = DateTime.Today; C. DateTime dt3 = DateTime.UtcNow; D. DateTime dt4 = DateTime.UtcToday; 5. Given the following code, which can display the day of the month expressed as an integral value between 1 and 31, as caption of label2? DateTime dt = DateTime::Today; A. label2->text = Convert::ToString(dt.Date); B. label2->text = Convert::ToString(dt.DayOfWeek); C. label2->text = Convert::ToString(dt.Day); D. label2->text = Convert::ToString(dt.DayOfYear); 6. Given the following code, which can convert the current time to a format of "10:46:06 PM"? DateTime dt = DateTime::Now; A. dt.tolocaltime() B. dt.tolongdatestring() C. dt.tolongtimestring() D. dt.toshortdatestring() 7. Which can get the current year value? A. DateTime::Now.Year B. DateTime::Year Visual C++ Programming Penn Wu, PhD 337

18 C. DateTime::CurrentYear D. DateTime::Year.Now 8. Which property of the TimeZone class gets the daylight saving time zone name? A. DaylightName B. DaylightValue C. CurrentDaylightName D. Daylight 9. Which can set the output of current date and time values to a format of "12 Aug, "? A. DateTime::Now.ToString("dd mmm, yyyy HH-mm-ss tt"); B. DateTime::Now.ToString("dd MMM, yyyy HH-mm-ss tt"); C. DateTime::Now.ToString("dd MMM, YYYY HH-mm-ss TT"); D. DateTime::Now.ToString("DD mmm, yyyy HH-MM-ss tt"); 10. Given the following code segment, which statement is correct? DaylightTime^ dt = gcnew DaylightTime(DateTime(2051,2,11), DateTime(2051,12,10), TimeSpan(2,0,0)); A. 2051,12,10 is the date and time when the daylight saving period begins. B. 2051,2,11 is the date and time when the daylight saving period ends. C. 2,0,0 is the difference between the standard time and the daylight saving time in ticks. D. 2,0,0 is the indicator of time zone in which the dayling saving time is going on. Visual C++ Programming Penn Wu, PhD 338

19 Lab #12 Handling Date and Time Values Learning Activity #1: Christmas Countdown 1. Launch the Developer Command Prompt (not the regular Command Prompt) and change to the C:\cis223 directory. 2. Use Notepad to create a new text file C:\cis223\lab12_1.cpp with the following contents: #using <System.Drawing.dll> using namespace System::Drawing; public ref class Form1: public Form Label^ label1; public: Form1() label1 = gcnew Label; label1->location = Point(10, 10); label1->size = Drawing::Size(300, 25); this->controls->add(label1); this->size = Drawing::Size(300,100); this->load += gcnew EventHandler(this, &Form1::Form1_Load); private: Void Form1_Load(Object^ sender, EventArgs^ e) DateTime dt = DateTime::Now; DateTime xmas = DateTime(DateTime::Now.Year, 12, 25); if ((xmas.dayofyear - dt.dayofyear) < 0) label1->text = "The " + DateTime::Now.Year + " Christmas has just passed!"; else label1->text = "Just " + (xmas.dayofyear - dt.dayofyear) + " day(s) to " + DateTime::Now.Year + " Christmas!"; ; [STAThread] int main() Application::Run(gcnew Form1); 3. Type cl /clr lab12_1.cpp /link /subsystem:windows /ENTRY:main and press [Enter] to compile. Test the program. A sample output looks: Visual C++ Programming Penn Wu, PhD 339

20 or 4. Download the assignment template, and rename it to lab12.doc if necessary. Capture a screen shot similar to the above figure and paste it to the Word document named lab12.doc (or.docx). Learning Activity #2: 1. In the C:\cis223 directory, use Notepad to create a new file named lab12_2.cpp with the following contents: #using <System.Drawing.dll> using namespace System::Drawing; public ref class Form1: public Form Label^ label1; Label^ label2; ListBox^ listbox1; public: Form1() label1 = gcnew Label; label1->location = Point(10, 10); label1->size = Drawing::Size(300, 25); this->controls->add(label1); label2 = gcnew Label; label2->location = Point(10, 50); label2->size = Drawing::Size(300, 25); this->controls->add(label2); listbox1 = gcnew ListBox; listbox1->location = Point(10, 60); listbox1->height = 150; listbox1->width = 250; listbox1->items->clear(); listbox1->items->add(""); listbox1->items->add("01. Hawaii"); listbox1->items->add("02. Alaska"); listbox1->items->add("03. Pacific Standard Time"); listbox1->items->add("04. Mountain Standard Time"); listbox1->items->add("05. Central Standard Time"); listbox1->items->add("06. Eastern Standard Time"); listbox1->items->add("07. Atlantic Standard Time"); this->controls->add(listbox1); Button^ button1 = gcnew Button; button1->text = "Convert"; button1->location = Point(10, 210); button1->size = Drawing::Size(80, 25); button1->click += gcnew EventHandler(this, &Form1::button1_Click); this->controls->add(button1); TimeZone^ tz = TimeZone::CurrentTimeZone; label1->text = "You are currently in the " + tz->standardname + ".\n" + Visual C++ Programming Penn Wu, PhD 340

21 "The time is " + DateTime::Now.ToString("t"); label2->text = "Select a different time zone"; private: Void button1_click(object^ sender, EventArgs^ e) if (listbox1->text!= "") // get the first two letters of selected item String^ str = Convert::ToString(listBox1->Text->Remove(2)); // change the hourly value to UTC time zone int utc_h = DateTime::Now.ToUniversalTime().Hour; int h; // variable represent destination hour //adjust time due to time zone offset based on UTC if (str == "01") h = utc_h - 10; else if (str == "02") h = utc_h - 8; else if (str == "03") h = utc_h - 7; else if (str == "04") h = utc_h - 6; else if (str == "05") h = utc_h - 5; else if (str == "06") h = utc_h - 4; else if (str == "07") h = utc_h - 3; //make sure hour value is between 0 and 23 if (h>=24) h=h-24; else if (h<0) h=h+24; //destination's AM-PM String^ ap; if (h>12) ap="pm"; else ap ="AM"; label2->text = "The destination time is " + h + ":" + Convert::ToString(DateTime::Now.Minute) + " " + ap; else MessageBox::Show("You must select an item."); ; [STAThread] int main() Application::Run(gcnew Form1); 2. Test the program. Visual C++ Programming Penn Wu, PhD 341

22 3. Capture a screen shot similar to the above figure and paste it to the Word document named lab12.doc (or.docx). Learning Activity #3: A Simple World Clock 1. In the C:\cis223 directory, use Notepad to create a new file named lab12_3.cpp with the following contents: #using <System.Drawing.dll> using namespace System::Drawing; public ref class Form1: public Form Label^ local; Label^ utc; Label^ London; Label^ Tokyo; DateTime dt; DateTime ut; //UTC date time DateTime ld; //London date time DateTime ty; //Tokyo date time TimeZoneInfo^ tz; public: Form1() this->size = Drawing::Size(300, 400); this->text = "Simple Word Clock"; tz = TimeZoneInfo::Local; dt = DateTime::Now; // current local time local = gcnew Label; local->text = "Local: " + dt.tostring("g") + "\n" + tz->displayname; local->autosize = true; local->location = Point(10, 10); Controls->Add(local); ut = DateTime::UtcNow; // current UTC date time utc = gcnew Label; utc->text = "UTC: " + ut.tostring("g"); utc->autosize = true; utc->location = Point(10, 110); Controls->Add(utc); ld = ut + TimeSpan(1, 0, 0); // London and UTC time zone offset: +1 hour London = gcnew Label; London->Text = "London: " + ld.tostring("g"); London->AutoSize = true; London->Location = Point(10, 210); Controls->Add(London); ty = ut + TimeSpan(9, 0, 0); // Tokyo and UTC time zone offset: +9 hour Visual C++ Programming Penn Wu, PhD 342

23 Tokyo = gcnew Label; Tokyo->Text = "Tokyo: " + ty.tostring("g"); Tokyo->AutoSize = true; Tokyo->Location = Point(10, 310); Controls->Add(Tokyo); Timer^ timer1 = gcnew Timer; timer1->tick += gcnew EventHandler(this, &Form1::timer1_Tick); timer1->interval = 1000; timer1->start(); private: System::Void timer1_tick(object^ sender, EventArgs^ e) tz = TimeZoneInfo::Local; dt = DateTime::Now; // current local time local->text = "Local: " + dt.tostring("g") + "\n" + tz->displayname; ut = DateTime::UtcNow; // current UTC date time utc->text = "UTC: " + ut.tostring("g"); ld = ut + TimeSpan(1, 0, 0); // London and UTC time zone offset: +1 hour London->Text = "London: " + ld.tostring("g"); ty = ut + TimeSpan(9, 0, 0); // Tokyo and UTC time zone offset: +9 hour Tokyo->Text = "Tokyo: " + ty.tostring("g"); ; [STAThread] int main() Application::Run(gcnew Form1); 2. Test the program. A sample output looks: 3. Capture a screen shot similar to the above figure and paste it to the Word document named lab12.doc (or.docx). Learning Activity #4: 1. In the C:\cis223 directory, use Notepad to create a new file named lab12_4.cpp with the following contents: Visual C++ Programming Penn Wu, PhD 343

24 #using <System.Drawing.dll> using namespace System::Drawing; public ref class Form1: public Form DateTimePicker^ datetimepicker1; Label^ label1; public: Form1() label1 = gcnew Label; label1->location = Point(10, 70); label1->size = Drawing::Size(300, 100); label1->text = "In Western calendar"; datetimepicker1 = gcnew DateTimePicker; datetimepicker1->location = Point(10, 10); Button^ button1 = gcnew Button; button1->text = "Go"; button1->location = Point(230, 10); button1->size = Drawing::Size(30, 25); button1->click += gcnew EventHandler(this, &Form1::button1_Click); Controls->Add(dateTimePicker1); Controls->Add(label1); Controls->Add(button1); this->size = Drawing::Size(300,300); private: Void button1_click(object^ sender, EventArgs^ e) int d = Convert::ToInt16(dateTimePicker1->Value.Day); int m = Convert::ToInt16(dateTimePicker1->Value.Month); int y = Convert::ToInt16(dateTimePicker1->Value.Year); ChineseLunisolarCalendar^ ch = gcnew ChineseLunisolarCalendar; DateTime dt = DateTime(y, m, d); // convert the picked date to DateTime format d = ch->getdayofmonth(dt); // convert to Chinese dayofmonth m = ch->getmonth(dt); // convert to Chinese month y = ch->getyear(dt); // convert to Chinese year DateTime ch1 = DateTime(y, m, d); // covert Chinese values to DateTime label1->text = "In Chinese Calendar:\n" + ch1.tolongdatestring(); ; [STAThread] int main() Application::Run(gcnew Form1); 2. Compile and test the program. Pick any date (any year), and click the Go button. A sample output looks: Visual C++ Programming Penn Wu, PhD 344

25 3. Capture a screen shot similar to the above figure and paste it to the Word document named lab12.doc (or.docx). Learning Activity #5: 1. In the C:\cis223 directory, use Notepad to create a new file named lab12_5.cpp with the following contents: int main() TimeZone^ tz = TimeZone::CurrentTimeZone; DaylightTime^ dt = tz->getdaylightchanges( DateTime::Now.Year ); String^ str = "In " + DateTime::Now.Year + ", the dayling saving time\n" + "\tstarts on : " + dt->start + "\n" + "\tends on : " + dt->end +"\n" + "\tdifference : " + dt->delta ; str += "\n\n"; DaylightTime^ dt2 = gcnew DaylightTime(DateTime(2051,2,11), DateTime(2051,12,10), TimeSpan(2,0,0)); str += "In 2051, the dayling saving time has been reset to\n" + "\tstarts on : " + dt2->start + "\n" + "\tends on : " + dt2->end +"\n" + "\tdifference : " + dt2->delta ; MessageBox::Show(str); 2. Test the program. 3. Capture a screen shot similar to the above figure and paste it to the Word document named lab12.doc (or.docx). Visual C++ Programming Penn Wu, PhD 345

26 Submittal 1. Complete all the 5 learning activities and the programming exercise in this lab. 2. Create a.zip file named lab12.zip containing ONLY the following self-executable files. lab12_1.exe lab12_2.exe lab12_3.exe lab12_4.exe lab12_5.exe lab12.doc (or lab12.docx or.pdf) [You may be given zero point if this Word document is missing] 3. Log in to Blackboard, and enter the course site. 4. Upload the zipped file to Question 11 of Assignment 12 as response. 5. Upload ex12.zip file to Question 12 as response. Note: You will not receive any credit if you submit file(s) to the wrong question. Programming Exercise 12: 1. Launch the Developer Command Prompt. 2. Use Notepad to create a new text file named ex12.cpp. 3. Add the following heading lines (Be sure to use replace [YourFullNameHere] with the correct one). //File Name: ex12.cpp //Programmer: [YourFullNameHere] 4. Write codes that will allow users to use a DateTimePicker control to pick any future date, countdown the days to that particular date, display the numbers of days to that date in a Label control. If the user picks a date in the past be sure to display Please pick a future date. On the Label control. 5. Compile the source code to produce executable code. and 6. Download the programming exercise template, and rename it to ex12.doc if necessary. Capture Capture a screen similar to the above figures and paste it to the Word document named ex12.doc (or.docx). 7. Compress the source file (ex12.cpp), executable code (ex12.exe), and Word document (ex12.doc) to a.zip file named ex12.zip. Grading criteria: You will earn credit only when the following requirements are fulfilled. No partial credit is given. You successfully submit both source file and executable file. Your source code must be fully functional and may not contain syntax errors in order to earn credit. Your executable file (program) must be executable to earn credit. Threaded Discussion Note: Students are required to participate in the thread discussion on a weekly basis. Student must post at least two messages as responses to the question every week. Each message must be posted on a different date. Grading is based on quality of the message. Question: Class, Visual C++ provides many classes with methods to handle data and time values. If you have to write an application for an travel agency which requires your application to be able to verify the "return date" given by a user is later than the "departure date". How would you solve this coding problem? If you can, provide an example to support your perspective. [There is never a right-orwrong answer for this question. Please free feel to express your opinion.] Visual C++ Programming Penn Wu, PhD 346

27 Be sure to use proper college level of writing. Do not use texting language. Visual C++ Programming Penn Wu, PhD 347