Calendar - monthly

< script >
//  SET ARRAYS
var day_of_week = new Array ( 'Sun' , 'Mon' , 'Tue' , 'Wed' , 'Thu' , 'Fri' , 'Sat' );
var month_of_year = new Array ( 'January' , 'February' , 'March' , 'April' , 'May' , 'June' , 'July' , 'August' , 'September' , 'October' , 'November' , 'December' );

//  DECLARE AND INITIALIZE VARIABLES
var Calendar = new Date ();

var year = Calendar.getYear();      // Returns year
var month = Calendar.getMonth();     // Returns month (0-11)
var today = Calendar.getDate();     // Returns day (1-31)
var weekday = Calendar.getDay();     // Returns day (1-31)

var DAYS_OF_WEEK = 7;     // "constant" for number of days in a week
var DAYS_OF_MONTH = 31;     // "constant" for number of days in a month
var cal;     // Used for printing

Calendar.setDate(1);     // Start the calendar day at '1'
Calendar.setMonth(month);     // Start the calendar month at now


/* VARIABLES FOR FORMATTING
NOTE: You can format the 'BORDER', 'BGCOLOR', 'CELLPADDING', 'BORDERCOLOR'
     tags to customize your caledanr's look. */

var TR_start = '<TR>' ;
var TR_end = '</TR>' ;
var highlight_start = '<TD WIDTH="30"><TABLE CELLSPACING=0 BORDER=1 BGCOLOR=DEDEFF BORDERCOLOR=CCCCCC><TR><TD WIDTH=20><B><CENTER>' ;
var highlight_end    = '</CENTER></TD></TR></TABLE></B>' ;
var TD_start = '<TD WIDTH="30"><CENTER>' ;
var TD_end = '</CENTER></TD>' ;

/* BEGIN CODE FOR CALENDAR
NOTE: You can format the 'BORDER', 'BGCOLOR', 'CELLPADDING', 'BORDERCOLOR'
tags to customize your calendar's look.*/

cal =   '<TABLE BORDER=1 CELLSPACING=0 CELLPADDING=0 BORDERCOLOR=BBBBBB><TR><TD>' ;
cal += '<TABLE BORDER=0 CELLSPACING=0 CELLPADDING=2>' + TR_start;
cal += '<TD COLSPAN="' + DAYS_OF_WEEK + '" BGCOLOR="#EFEFEF"><CENTER><B>' ;
cal += month_of_year[month]   + '   ' + year + '</B>' + TD_end + TR_end;
cal += TR_start;

//   DO NOT EDIT BELOW THIS POINT  //

// LOOPS FOR EACH DAY OF WEEK
for (index = 0; index < DAYS_OF_WEEK; index ++ )
{

// BOLD TODAY'S DAY OF WEEK
if (weekday == index)
cal += TD_start + '<B>' + day_of_week[index] + '</B>' + TD_end;

// PRINTS DAY
else
cal += TD_start + day_of_week[index] + TD_end;
}

cal += TD_end + TR_end;
cal += TR_start;

// FILL IN BLANK GAPS UNTIL TODAY'S DAY
for (index = 0; index < Calendar.getDay(); index ++ )
cal += TD_start + '  ' + TD_end;

// LOOPS FOR EACH DAY IN CALENDAR
for (index = 0; index < DAYS_OF_MONTH; index ++ )
{
if ( Calendar.getDate() > index )
{
  // RETURNS THE NEXT DAY TO PRINT
 week_day = Calendar.getDay();

  // START NEW ROW FOR FIRST DAY OF WEEK
  if (week_day == 0)
 cal += TR_start;

  if (week_day != DAYS_OF_WEEK)
  {

  // SET VARIABLE INSIDE LOOP FOR INCREMENTING PURPOSES
  var day   = Calendar.getDate();

  // HIGHLIGHT TODAY'S DATE
  if ( today == Calendar.getDate() )
 cal += highlight_start + day + highlight_end + TD_end;

  // PRINTS DAY
  else
 cal += TD_start + day + TD_end;
  }

  // END ROW FOR LAST DAY OF WEEK
  if (week_day == DAYS_OF_WEEK)
 cal += TR_end;
  }

  // INCREMENTS UNTIL END OF THE MONTH
 Calendar.setDate(Calendar.getDate() + 1);

} // end for loop

cal += '</TD></TR></TABLE></TABLE>' ;

//  PRINT CALENDAR
document.write(cal);

</ script >

//Thanks to David Pye for his JavaScript Vault contribution