ADD DATE AND TIME TO YOUR WEB PAGES

JavaScript includes several built-in objects such as the Math object and the String object from previous lessons, and the Date object.

To create a new Date object:

var myDate = new Date();

The Date object can return date and time in many different forms, depending on the arguments (parameters) you provide. For example, if you display the variable myDate in an alert box:

var myDate = new Date();
alert (myDate);

The display varies depending on the browser. Figure 5.1 shows the alert box in Internet Explorer 6, and, as you can see, it includes day of the week, month, day of the month, hours, minutes, seconds, local time zone, and year.

Figure 5-1: Displaying the Date in Internet Explorer.

Figure 5-2 shows the same code displayed in Netscape 7. It displays in this order: day of the week, month, day of the month, year, hours, minutes, seconds, and local time zone.

Figure 5-2: Displaying the Date in Netscape.

You can provide parameters so that the date displays with specific values:

• yyyy,mm,dd: Displays date with these parameters for year, month, and day, the rest of the parameters are set to zero

// new Date (2003,9,12);

• yyyy,mm,dd,hh,mm,ss: Adds specified hours, months, and seconds to the previous display

// new Date (2003,9,12,3,15,30);

• milliseconds: Displays date based on number of milliseconds after the epoch

// new Date (7964000039);

This displays a date of Apr 2 21:13:20 1970