function isBlankValue(elem){
	if (!elem.value) return true; 
	else {var str = elem.value;
	for (var i = 0; i < str.length; i++) {
		var ch = str.charAt(i);
		if ((ch != ' ') && (ch != '\n') && (ch != '\t')) return false;}
		return true;}
}

function checkEmailAddress(field){
	if (field.value != ''){
		var value = String(field.value);
		var passed = false;

		for (index = 0; index < value.length; index++){
			if (value.charAt(index) == '@')
				passed = true;
		}

		if (passed == false){
			alert('Please use {ie. username@domain.com} format for all email entries.');
			field.value = '';
			field.focus();
		}
	}
}

/******************************* functions to check radio and checkbox values */


function getFormGroup(name) {
	return document.getElementsByName(name);
}

function isChecked(name) {		/* return whether or not any value is checked */
elements = getFormGroup(name);
if (elements)					
for (i = 0; i < elements.length; i++)
if (elements[i].checked)
return true;
return false;					
}


function checkIt()
{
	var formObj = document.speakerProposal;
	var count = 0;
	for (i=0; i<formObj.length; i++)
		{
			if(formObj.elements[i].type == 'checkbox')
			if(formObj.elements[i].checked)
			count++;
		}
	if (count >= 1)
		{
		return true;
	}
}

/******************************* function to check form */

function checkFormData(frm){
	var al = isChecked('question_10')? true : false;
	var at = isChecked('question_12')? true : false;
	var da = checkIt()? true : false;
	var sError = '';
	frm.SubmitButton.disabled=true;
	if (da == false) sError += " - Please check a date you are available\n";
	if (frm.person_first_name.value == "") sError += " - Please enter your first name\n";
	if (frm.person_last_name.value == "") sError += " - Please enter your last name\n";
	if (frm.person_title.value == "") sError += " - Please enter your job title\n";
	if (frm.person_company.value == "") sError += " - Please enter your company\n";
	if (frm.person_phone.value == "") sError += " - Please enter your phone number\n";
	if (frm.person_email.value == "") sError += " - Please enter your email address\n";
	if (frm.person_city.value == "") sError += " - Please enter your city\n";
	if (frm.person_state.value == "") sError += " - Please enter your state\n";
	if (frm.question_2_OTHERTEXT.value == "") sError += " - Please enter the title for your event\n";
	if (frm.question_3_OTHERTEXT.value == "") sError += " - Please describe the issue your event will address\n";
	if (frm.question_4_OTHERTEXT.value == "") sError += " - Please describe how your presentation will address the issue\n";
	if (frm.question_5_OTHERTEXT.value == "") sError += " - Please describe the interest to attendees\n";
	if (frm.question_6_OTHERTEXT.value == "") sError += " - Please list your objectives\n";
	if (frm.question_7_OTHERTEXT.value == "") sError += " - Please list at least one target audience\n";
	if (al == false) sError += " - Please indicate the audience level\n";
	if (frm.question_11_OTHERTEXT.value == "") sError += " - Please list what your audience should know beforehand or write None\n";
	if (at == false) sError += " - Please indicate if you will be inviting attendees\n";
	if (frm.question_14_OTHERTEXT.value == "") sError += " - Please highlight your background or education\n";
	if (frm.question_15_OTHERTEXT.value == "") sError += " - Please highlight your speaking experience\n"
	if (frm.question_16_OTHERTEXT.value == "") sError += " - Please describe your organization\n";
	if (frm.question_17_OTHERTEXT.value == "") sError += " - If you do not have sponsers, please write None\n";
	if (frm.question_18_OTHERTEXT.value == "") sError += " - Please sign the disclosure by typing your first and last name\n";
	if (sError.length > 0){alert('Please correct the following errors:\n\n' + sError); 
	frm.SubmitButton.disabled=false; 
	return false; }
return true;
}