/*
Usar: onkeypress="return solo_numerico(this,event)"
dec = true es para permitir ingresar puntos
*/
function solo_numerico(myfield, e, dec){
	var key;
	var keychar;
	
	if (window.event)
	   key = window.event.keyCode;
	else if (e)
	   key = e.which;
	else
	   return true;
	keychar = String.fromCharCode(key);
	
	// control keys
	if ((key==null) || (key==0) || (key==8) || 
	    (key==9) || (key==13) || (key==27) )
	   return true;
	
	// numbers
	else if ((("0123456789-").indexOf(keychar) > -1))
	   return true;
	
	// decimal point jump
	else if (dec && (keychar == ".")){
	   myfield.form.elements[dec].focus();
	   return false;
	}else
	   return false;
}

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

// return the value of the radio button that is checked
// return an empty string if none are checked, or
// there are no radio buttons
function getCheckedValue(radioObj) {
	if(!radioObj)
		return "";
	var radioLength = radioObj.length;
	if(radioLength == undefined)
		if(radioObj.checked)
			return radioObj.value;
		else
			return "";
	for(var i = 0; i < radioLength; i++) {
		if(radioObj[i].checked) {
			return radioObj[i].value;
		}
	}
	return "";
}