// Checks for empty contact form data

function validate_required(field,alerttxt) {
	with (field) {
		if (value == null || value == "") {
			alert(alerttxt);
			return false
			}
		else {
			return true
		}
	}
}

function validate_email(field,alerttxt) {
	with (field) {
		apos=value.indexOf("@")
		dotpos=value.lastIndexOf(".")
		if (apos <1 || dotpos-apos < 2) {
			alert(alerttxt);
			return false
		}
		else {
			return true
		}
	}
}

function validate_form(thisform) {
	with (thisform)	{
		if (validate_required(username,"Please enter your name !")==false) {
		 	username.focus();
			return false
		}
		if (validate_required(email,"Please enter your email address !")==false) {
		 	email.focus();
			return false
		}
		if (validate_email(email,"Your e-mail address is not valid !")==false) {
			email.focus();
			return false
		}
		if (validate_required(location,"Please enter your location !")==false) {
		 	location.focus();
			return false
		}
		if (validate_required(comments,"Please enter your comments !")==false) {
		 	comments.focus();
			return false
		}
	}
}