Question

The js below reveals a div based on the amount(size) of checkboxes vselected and it works fine. The checkboxes themselves are consecutive dates. What I need is to make sure that the dates selected are in consecutive order – ie 07/04, 07/05, 07/06 e.t.c. If the dates are not in consecutive order then the div does not reveal(show).

$('input[type=checkbox]').change(function(){
   if($('input:checked').size() > 4){
     $("#hideocrp").show();   
   }
   else {
     $('#hideocrp').hide()   
   }
});

Answer 1

You can use the following code to achieve your goals:

var start = false;
var checkstart = false;
$('#hideocrp').hide();
$('input[type=checkbox]').change(function () {
  checkstart = false;
  start = false;
  $('input[type=checkbox]').each(function () {
    if ($(this).is(":checked")) {
      var index = $(this).index("input[type=checkbox]");
      if (start == false) {
        start = index + 1;
      }
      if (index == start - 1) {
        start = start + 1;
        checkstart++;
      } else {
        checkstart = false;
        return false;
      }
    }
  });
  if (checkstart > 3) {
    $("#hideocrp").show();
  } else {
    $('#hideocrp').hide();
  }
});

Live demo | Demo source

Edit:
Try using this code to do a relaxed search of a consecutive checkbox match.

var start = false;
var checkstart = false;
$('#hideocrp').hide();
$('input[type=checkbox]').change(function () {
  checkstart = 0;
  start = false;
  $('input[type=checkbox]').each(function () {
    if ($(this).is(":checked")) {
      var index = $(this).index("input[type=checkbox]");
      if (index == 0) {
        start = index+1;
      }
      if (index == start+1) {
        start = start + 1;
        checkstart++;
      } else {
        if (checkstart < 4) {
          checkstart = 1;
          start = index;
        } else {
          return false;
        }
      }
    }
  });
  if (checkstart > 3) {
    $("#hideocrp").show();
  } else {
    $('#hideocrp').hide();
  }
});

Live demo | Demo source

Edit2:

To solve your second issue, just use

$(document).ready(function() {
  $('input[type=checkbox]').trigger("change");
});

Demo | Source

To test against