function clearText(field){

    if (field.defaultValue == field.value) field.value = '';
    else if (field.value == '') field.value = field.defaultValue;

}

function validate(address) {
   var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
   if(reg.test(address) == false) {
     //alert('Invalid Email Address');
      return false;
   } else {
		return true;   
   }
}

function validateForm()
{

	document.getElementById('naam').value
	document.getElementById('emailadres').value
	document.getElementById('straat').value
	document.getElementById('postcode').value
	document.getElementById('woonplaats').value
	
	vError = 0;
	if(document.getElementById('naam').value == "Naam" || !document.getElementById('naam').value)
	{
		document.getElementById('naam').style.color = "#FF0000";
		document.getElementById('naam').style.fontWeight = "bold";
		vError++;
	} else {
		document.getElementById('naam').style.color = "#000000";
		document.getElementById('naam').style.fontWeight = "normal";
	}
	
	if(document.getElementById('emailadres').value == "Emailadres" || !document.getElementById('emailadres').value || !validate(document.getElementById('emailadres').value))
	{
		document.getElementById('emailadres').style.color = "#FF0000";
		document.getElementById('emailadres').style.fontWeight = "bold";
		vError++;
	} else {
		document.getElementById('emailadres').style.color = "#000000";
		document.getElementById('emailadres').style.fontWeight = "normal";
	}
	
	if(document.getElementById('straat').value == "Straat + nummer" || !document.getElementById('straat').value)
	{
		document.getElementById('straat').style.color = "#FF0000";
		document.getElementById('straat').style.fontWeight = "bold";
		vError++;
	} else {
		document.getElementById('straat').style.color = "#000000";
		document.getElementById('straat').style.fontWeight = "normal";
	}
	
	if(document.getElementById('postcode').value == "Postcode" || !document.getElementById('postcode').value)
	{
		document.getElementById('postcode').style.color = "#FF0000";
		document.getElementById('postcode').style.fontWeight = "bold";
		vError++;
	} else {
		document.getElementById('postcode').style.color = "#000000";
		document.getElementById('postcode').style.fontWeight = "normal";
	}
	
	if(document.getElementById('woonplaats').value == "Woonplaats" || !document.getElementById('woonplaats').value)
	{
		document.getElementById('woonplaats').style.color = "#FF0000";
		document.getElementById('woonplaats').style.fontWeight = "bold";
		vError++;
	} else {
		document.getElementById('woonplaats').style.color = "#000000";
		document.getElementById('woonplaats').style.fontWeight = "normal";
	}
	
	
	if(vError > 0)
	{
		return false;
	} else {
		return true;
	}

}