// valid selector from dropdown list
function checkDropdown(it, choice) {
	var error = "";
    if (choice == 0) {
    	error = "You didn't choose an option from the "+it+" drop-down list.\n";
    }    
	return error;
}
//valid email add
function checkEmail (strng) {
	var error="";
	if (strng == "") {
   		error = "You didn't enter an email address.\n";
	}

    var emailFilter=/^.+@.+\..{2,3}$/;
    if (!(emailFilter.test(strng))) { 
       error = "Please enter a valid email address.\n";
    } else {//test email for illegal characters
    	var illegalChars= /[\(\)\<\>\,\;\:\\\"\[\]]/
        if (strng.match(illegalChars)) {
        	error = "The email address contains illegal characters.\n";
        }
    }
	return error;    
}
// non-empty textbox
function isEmpty(it,strng) {
	var error = "";
	if (strng.length == 0) {
    	error = "The mandatory text area, "+ it +", has not been filled in.\n"
	}
	return error;	  
}
// phone number - strip out delimiters
function checkPhone (strng) {
	var error = "";
	if (strng == "") {
		error = "You didn't enter a phone number.\n";
	} else {
		var stripped = strng.replace(/[\(\)\.\-\ ]/g, ''); //strip out acceptable non-numeric characters
    	if (isNaN(parseInt(stripped))) {
       		error = "The phone number contains illegal characters.\n";  
    	} 
	}
	return error;
}