//checkt of de velden zijn ingevuld
function check_Form(formulier, fields, description) {

	d = document.forms [formulier];
	var errors = "";
	var data_field = "";
	//var description = new Array();
	
	for (i=0;i<fields.length;i++){ 
		data_field = fields[i];
		//alert(data_field);
		//if(data_field) {
			//if(d [data_field]) {
				if(d [data_field].length && d [data_field].type!="select-one") { // radio or checkbox and no select?
					array_errors = true;
					for (y=0;y<d [data_field].length;y++) { // get options
						if(d [data_field][y].checked == true) {
							array_errors = false;
						}
					}
					if(array_errors != false){
						errors += "- "+description[i]+"\n";
					}
				}		
				else if(d [data_field].type=="checkbox"){
					if(d [data_field].checked == false){
						errors += "- "+description[i]+"\n";
					}
				}
				else {
					if(d [data_field].value == "") {
						errors += "- "+description[i]+"\n";
					}
				}
		
				if( d [data_field].name == "email"){
					if( checkEmail("email") == false){
						errors += "- "+description[i]+"\n";
					}
				}
			//}
		//}
	}
	
	
	if(errors) {
		alert("De volgende veld(en) zijn nog niet (correct) ingevuld:\n"+errors);
		return false;
	}
	else {
		return true;
	}
}


function checkEmail(emailadres) {
	//var email = document.getElementById('emailaddress');
	var email = document.getElementById(emailadres);
	if(email) {
		var filter = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
		if (!filter.test(email.value)) {
			//alert('Please provide a valid email address');
			//email.focus
			return false;
		}
		return true;
	} else {
		return true;
	}
	
}