NN 2, IE 3
You want your page to include a greeting pertinent to the user's part of the day, such as "Good morning" or "Good afternoon".
First, create a function that returns strings associated with each day part, as calculated by a fresh Date object:
function dayPart( ) { var oneDate = new Date( ); var theHour = oneDate.getHours( ); if (theHour < 12) { return "morning"; } else if (theHour < 18) { return "afternoon"; } else { return "evening"; } }
To accommodate both scriptable and unscriptable browsers, be sure to encase the script statement inside HTML comment tags, and include the noscript element with the text to display for unscriptable browsers.
<script language="JavaScript" type="text/javascript"> <!-- document.write("Good " + dayPart( ) + " and welcome") //--> </script> <noscript>Welcome</noscript> to GiantCo.
As the page loads, it creates an instance of a Date object. By omitting the parameter for the Date object constructor function, the current time and date are used to generate the object. A Date object instance is not a ticking clock, but rather a snapshot of the clock when the object was created. The accuracy of the time is strictly dependent upon the computer's internal clock setting.
A Date object has numerous functions for getting and setting components of the date, ranging from the millisecond to the year. The getHours( ) method used in the Solution returns a number between 0 and 23, corresponding to the 24-hour clock set to the user's local time. The dayPart( ) function simply divides the day into three portions, breaking at noon and 6 P.M. to supply day parts ranging through morning, afternoon, and evening.
Recipe 2.9 through Recipe 2.11 for information about working with the Date object.