using a calendar script, how to prevent old date selected

[jasonc]

I have this code which is a calendar popup script.

 

How do I prevent a user from selecting an old date.

 

How can the old date numbers be disabled?

 

// <!-- <![CDATA[

// Project: Dynamic Date Selector (DtTvB) - 2006-03-16
// Script featured on JavaScript Kit- http://www.javascriptkit.com
// Code begin...
// Set the initial date.
var ds_i_date = new Date();
ds_c_month = ds_i_date.getMonth() + 1;
ds_c_year = ds_i_date.getFullYear();

// Get Element By Id
function ds_getel(id) {
return document.getElementById(id);
}

// Get the left and the top of the element.
function ds_getleft(el) {
var tmp = el.offsetLeft;
el = el.offsetParent
while(el) {
	tmp += el.offsetLeft;
	el = el.offsetParent;
}
return tmp;
}
function ds_gettop(el) {
var tmp = el.offsetTop;
el = el.offsetParent
while(el) {
	tmp += el.offsetTop;
	el = el.offsetParent;
}
return tmp;
}

// Output Element
var ds_oe = ds_getel('ds_calclass');
// Container
var ds_ce = ds_getel('ds_conclass');

// Output Buffering
var ds_ob = ''; 
function ds_ob_clean() {
ds_ob = '';
}
function ds_ob_flush() {
ds_oe.innerHTML = ds_ob;
ds_ob_clean();
}
function ds_echo(t) {
ds_ob += t;
}

var ds_element; // Text Element...

var ds_monthnames = [
'January', 'February', 'March', 'April', 'May', 'June',
'July', 'August', 'September', 'October', 'November', 'December'
]; // You can translate it for your language.

var ds_daynames = [
'Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'
]; // You can translate it for your language.

// Calendar template
function ds_template_main_above(t) {
return '<table cellpadding="3" cellspacing="1" class="ds_tbl">'
     + '<tr>'
	 + '<td class="ds_head" style="cursor: pointer" onclick="ds_py();"><<</td>'
	 + '<td class="ds_head" style="cursor: pointer" onclick="ds_pm();"><</td>'
	 + '<td class="ds_head" style="cursor: pointer" onclick="ds_hi();" colspan="3">[Close]</td>'
	 + '<td class="ds_head" style="cursor: pointer" onclick="ds_nm();">></td>'
	 + '<td class="ds_head" style="cursor: pointer" onclick="ds_ny();">>></td>'
	 + '</tr>'
     + '<tr>'
	 + '<td colspan="7" class="ds_head">' + t + '</td>'
	 + '</tr>'
	 + '<tr>';
}

function ds_template_day_row(t) {
return '<td class="ds_subhead">' + t + '</td>';
// Define width in CSS, XHTML 1.0 Strict doesn't have width property for it.
}

function ds_template_new_week() {
return '</tr><tr>';
}

function ds_template_blank_cell(colspan) {
return '<td colspan="' + colspan + '"></td>'
}

function ds_template_day(d, m, y) {
return '<td class="ds_cell" onclick="ds_onclick(' + d + ',' + m + ',' + y + ')">' + d + '</td>';
// Define width the day row.
}

function ds_template_main_below() {
return '</tr>'
     + '</table>';
}

// This one draws calendar...
function ds_draw_calendar(m, y) {
// First clean the output buffer.
ds_ob_clean();
// Here we go, do the header
ds_echo (ds_template_main_above(ds_monthnames[m - 1] + ' ' + y));
for (i = 0; i < 7; i ++) {
	ds_echo (ds_template_day_row(ds_daynames[i]));
}
// Make a date object.
var ds_dc_date = new Date();
ds_dc_date.setMonth(m - 1);
ds_dc_date.setFullYear(y);
ds_dc_date.setDate(1);
if (m == 1 || m == 3 || m == 5 || m == 7 || m == 8 || m == 10 || m == 12) {
	days = 31;
} else if (m == 4 || m == 6 || m == 9 || m == 11) {
	days = 30;
} else {
	days = (y % 4 == 0) ? 29 : 28;
}
var first_day = ds_dc_date.getDay();
var first_loop = 1;
// Start the first week
ds_echo (ds_template_new_week());
// If sunday is not the first day of the month, make a blank cell...
if (first_day != 0) {
	ds_echo (ds_template_blank_cell(first_day));
}
var j = first_day;
for (i = 0; i < days; i ++) {
	// Today is sunday, make a new week.
	// If this sunday is the first day of the month,
	// we've made a new row for you already.
	if (j == 0 && !first_loop) {
		// New week!!
		ds_echo (ds_template_new_week());
	}
	// Make a row of that day!
	ds_echo (ds_template_day(i + 1, m, y));
	// This is not first loop anymore...
	first_loop = 0;
	// What is the next day?
	j ++;
	j %= 7;
}
// Do the footer
ds_echo (ds_template_main_below());
// And let's display..
ds_ob_flush();
// Scroll it into view.
// ds_ce.scrollIntoView(); // I removed this to stop the scrolling to top of page !!!!
}

// A function to show the calendar.
// When user click on the date, it will set the content of t.
function ds_sh(t) {
// Set the element to set...
ds_element = t;
// Make a new date, and set the current month and year.
var ds_sh_date = new Date();
ds_c_month = ds_sh_date.getMonth() + 1;
ds_c_year = ds_sh_date.getFullYear();
// Draw the calendar
ds_draw_calendar(ds_c_month, ds_c_year);
// To change the position properly, we must show it first.
ds_ce.style.display = '';
// Move the calendar container!
the_left = ds_getleft(t);
the_top = ds_gettop(t) + t.offsetHeight;
ds_ce.style.left = the_left + 'px';
ds_ce.style.top = the_top + 'px';
// Scroll it into view.
// ds_ce.scrollIntoView(); // I removed this to stop the scrolling to top of page !!!!
}

// Hide the calendar.
function ds_hi() {
ds_ce.style.display = 'none';
}

// Moves to the next month...
function ds_nm() {
// Increase the current month.
ds_c_month ++;
// We have passed December, let's go to the next year.
// Increase the current year, and set the current month to January.
if (ds_c_month > 12) {
	ds_c_month = 1; 
	ds_c_year++;
}
// Redraw the calendar.
ds_draw_calendar(ds_c_month, ds_c_year);
}

// Moves to the previous month...
function ds_pm() {
ds_c_month = ds_c_month - 1; // Can't use dash-dash here, it will make the page invalid.
// We have passed January, let's go back to the previous year.
// Decrease the current year, and set the current month to December.
if (ds_c_month < 1) {
	ds_c_month = 12; 
	ds_c_year = ds_c_year - 1; // Can't use dash-dash here, it will make the page invalid.
}
// Redraw the calendar.
ds_draw_calendar(ds_c_month, ds_c_year);
}

// Moves to the next year...
function ds_ny() {
// Increase the current year.
ds_c_year++;
// Redraw the calendar.
ds_draw_calendar(ds_c_month, ds_c_year);
}

// Moves to the previous year...
function ds_py() {
// Decrease the current year.
ds_c_year = ds_c_year - 1; // Can't use dash-dash here, it will make the page invalid.
// Redraw the calendar.
ds_draw_calendar(ds_c_month, ds_c_year);
}

// Format the date to output.
function ds_format_date(d, m, y) {
// 2 digits month.
m2 = '00' + m;
m2 = m2.substr(m2.length - 2);
// 2 digits day.
d2 = '00' + d;
d2 = d2.substr(d2.length - 2);
// YYYY-MM-DD
// return y + '-' + m2 + '-' + d2;
return d2 + '-' + m2 + '-' + y;
}

// When the user clicks the day.
function ds_onclick(d, m, y) {
// Hide the calendar.
ds_hi();
// Set the value of it, if we can.
if (typeof(ds_element.value) != 'undefined') {
	ds_element.value = ds_format_date(d, m, y);
// Maybe we want to set the HTML in it.
} else if (typeof(ds_element.innerHTML) != 'undefined') {
	ds_element.innerHTML = ds_format_date(d, m, y);
// I don't know how should we display it, just alert it to user.
} else {
	alert (ds_format_date(d, m, y));
}
}

// And here is the end.

// ]]> -->

[Adam]

Within the "db_onclick()" function, you have the d, m and y parameters containing the selected date, and a global date object called ds_i_date you can use to get the current d, m and y. Using those you should be able to validate the date isn't before the current date.

 

// When the user clicks the day.

function ds_onclick(d, m, y) {

  // Hide the calendar.

  ds_hi();

  // Set the value of it, if we can.

  if (typeof(ds_element.value) != 'undefined') {

      ds_element.value = ds_format_date(d, m, y);

  // Maybe we want to set the HTML in it.

  } else if (typeof(ds_element.innerHTML) != 'undefined') {

      ds_element.innerHTML = ds_format_date(d, m, y);

  // I don't know how should we display it, just alert it to user.

  } else {

      alert (ds_format_date(d, m, y));

  }

}

// Code begin...

// Set the initial date.

var ds_i_date = new Date();

[Psycho]

You *can* prevent the popup calendar from allowing the user to input previous dates as well. But, I would definitely use MrAdams solution as well.

 

By the way, the code you are using has an error in the logic to determine the number of days in February:

	if (m == 1 || m == 3 || m == 5 || m == 7 || m == 8 || m == 10 || m == 12) {
	days = 31;
} else if (m == 4 || m == 6 || m == 9 || m == 11) {
	days = 30;
} else {
	days = (y % 4 == 0) ? 29 : 28;
}

 

That formula for determining days in february is not correct. It should be this

		days = (y%4==0 && (y%100!=0 || y%400==0)) ? 29 : 28;

 

To disable the prior year or month links when they would take you to a period before the current date replace the ds_template_main_above() function with this:

function ds_template_main_above(t) {
return '<table cellpadding="3" cellspacing="1" class="ds_tbl">'
     + '<tr>'
	//Prior Year link
	 + ((new Date(ds_c_year-1, ds_c_month, 1)<ds_i_date)
	    ? '<td class="ds_head" style="color: #cecece"><<</td>'
	    : '<td class="ds_head" style="cursor: pointer" onclick="ds_py();"><<</td>')
	//Prior Month link
	 + ((new Date(ds_c_year, ds_c_month-1, 1)<ds_i_date)
	    ? '<td class="ds_head" style="color: #cecece"><</td>'
	    : '<td class="ds_head" style="cursor: pointer" onclick="ds_pm();"><</td>')
	 + '<td class="ds_head" style="cursor: pointer" onclick="ds_hi();" colspan="3">[Close]</td>'
	 + '<td class="ds_head" style="cursor: pointer" onclick="ds_nm();">></td>'
	 + '<td class="ds_head" style="cursor: pointer" onclick="ds_ny();">>></td>'
	 + '</tr>'
     + '<tr>'
	 + '<td colspan="7" class="ds_head">' + t + '</td>'
	 + '</tr>'
	 + '<tr>';
}

 

Then to prevent a day within the currently displayed month from being selected when it is before the current day, change the ds_template_day() function to this:

function ds_template_day(d, m, y) {
if (new Date(y, m-1, d)>=ds_i_date)
{
	return '<td class="ds_cell" onclick="ds_onclick('+d+','+m +','+y+');">' + d + '</td>';
}
else
{
	return '<td class="ds_cell" style="cursor:auto;color: #cecece">' + d + '</td>';
}
}