Created: 12/16/2001

Checkbox Validator

Just a simple script to do validation for checkboxes. It validates user input to assure that there aren't too many checked, and not too few chosen.

Source code for the function at the bottom of the page.

What is Your Industry?
[ You must select at least 1 and no more than 6 for this question. ]












































































































The Source Code of the Function: (this goes in the <head> of the document)

<script type="text/javascript" language="JavaScript">
/*
   written by joe crawford, for fun.
   it's friday!	
   12/14/2001.
*/
function howManyChecked(whichForm,whichCheckBoxArray,myMax,myMin,whichQuestion)
/*
  This function takes 5 paramaters:
  whichForm -- the NAME of the form to be validated, a string
  whichCheckBoxArray -- the NAME of the checkbox to be checked, a string
  myMax -- the most you want the user to be able to check, an integer
  myMin -- the least you want the user to be able to check, an integer
  whichQuestion -- a short description of the question, a string
  
  example use:
  howManyChecked('myform','cb_industry',6,1,'Industry');
*/
{
	var _countChecked = 0;
	var err = 0;
	/* iterate through all the elements in the checkbox array */
	for(i=0;i<document[whichForm][whichCheckBoxArray].length;i++)
	{
		/* and check to see if each is checked */
		if(document[whichForm][whichCheckBoxArray][i].checked==true)
			/* if it is, increment a counter */
			{ _countChecked++; }
	}
	/* is the count too high? */
	if(_countChecked > myMax)
		{ alert('Limit '+myMax+' checks for the '+whichQuestion+' question.');
			err = 1;}
	/* of is the count too low */
	else if(_countChecked < myMin)
		{ alert('You must fill out at least '+myMin+' entry(s) for the '+whichQuestion+' question.');
			err = 1;}
	if (err == 1) { return false; }
}

</script>

The Source Code for invoking it: (this goes in <form> tag)

<form
	action="https://www.artlung.com/"
	name="myform"
	onsubmit="return howManyChecked('myform','cb_industry',6,1,'Industry');">

Source Code

<script type="text/javascript" language="JavaScript">
/*
   written by joe crawford for fun.
   it's friday!	  
   12/14/2001.
*/
function howManyChecked(whichForm,whichCheckBoxArray,myMax,myMin,whichQuestion)
/*
  This function takes 5 paramaters:
  whichForm -- the NAME of the form to be validated, a string
  whichCheckBoxArray -- the NAME of the checkbox to be checked, a string
  myMax -- the most you want the user to be able to check, an integer
  myMin -- the least you want the user to be able to check, an integer
  whichQuestion -- a short description of the question, a string
  
  example use:
  howManyChecked('myform','cb_industry',6,1,'Industry');
*/
{
	var _countChecked = 0;
	var err = 0;
	/* iterate through all the elements in the checkbox array */
	for(i=0;i<document[whichForm][whichCheckBoxArray].length;i++)
	{
		/* and check to see if each is checked */
		   if(document[whichForm][whichCheckBoxArray][i].checked==true)
				/* if it is, increment a counter */
				      { _countChecked++; }
				      }
				      /* is the count too high? */
				      if(_countChecked > myMax)
						       { alert('Limit '+myMax+' checks for the '+whichQuestion+' question.');
								      err = 1;}
								      /* of is the count too low */
								      else if(_countChecked < myMin)
									   { alert('You must fill out at least '+myMin+' entry(s) for the '+whichQuestion+' question.');
											err = 1;}
											if (err == 1) { return false; }
}

</script>