Source code for leapyear.js

// LeapYear.js,  Version 1.01 for Windows Script Host

// Check if the specified year is a leap year.

//

// Written by Rob van der Woude

// http://www.robvanderwoude.com

// Parse command line

objArgs = WScript.Arguments;

if ( objArgs.length == 0 ) {

	// Default is current year

	objToday = new Date();

	myYear = objToday.getFullYear();

};

if ( objArgs.length == 1 ) {

	// Check datatype and range of argument

	myYear = objArgs(0).valueOf( );

	if ( isNaN( myYear ) ) Syntax( );

	if ( myYear <    0 )   Syntax( );

	if ( myYear > 9999 )   Syntax( );

};

if ( objArgs.length > 1 ) Syntax( );

isLeapYear = 0;

if ( myYear %   4 == 0 ) isLeapYear = 1;

if ( myYear % 100 == 0 ) isLeapYear = 0;

if ( myYear % 400 == 0 ) isLeapYear = 1;

if ( isLeapYear == 1 ) {

	strIs = " IS";

} else {

	strIs = " is NOT";

};

WScript.Echo( myYear + strIs + " a leap year" );

// Done

WScript.Quit( isLeapYear );

function Syntax( ) {

WScript.Echo( );

WScript.Echo( "LeapYear.js,  Version 1.01 for WSH" );

WScript.Echo( "Check if the specified year is a leap year." );

WScript.Echo( );

WScript.Echo( "Usage:   CScript  LEAPYEAR.JS  [ year ]" );

WScript.Echo( );

WScript.Echo( "Where:   'year' should be within the range of 0 through 9999." );

WScript.Echo( "         Default is the current year, if none is specified." );

WScript.Echo( );

WScript.Echo( "Returns: 0  if NOT a leap year" );

WScript.Echo( "         1  on leap years" );

WScript.Echo( "         2  on syntax errors" );

WScript.Echo( );

WScript.Echo( "Written by Rob van der Woude" );

WScript.Echo( "http://www.robvanderwoude.com" );

WScript.Quit(2);

}