//limpia el conenido del formulario
function borrar() {
    for (i = 0; i < document.forms[0].length; i++) {
        doc = document.forms[0].elements[i];
        switch (doc.type) {
            case "text":
                doc.value = "";
                var img = document.getElementById("img_" + doc.name);
                if (img != null) {
                    img.style.visibility = "hidden";
                    img.style.display = "none";
                }
                if ((doc.name.indexOf("numExpDGest") >= 0)||(doc.name.indexOf("numProDGest") >= 0)) {
                    var anyActual = new Date();
                    var stringAny = anyActual.getFullYear().toString();
                    if ((stringAny != null) && (stringAny != "")) {
                        doc.value = stringAny.toString().substring(2) + "-";
                    }
                }
                break;
            case "checkbox":
                doc.checked = false;
                break;
            case "radio":
                doc.checked = false;
                break;
            case "textarea":
                doc.value = "";
                break;
            case "select-one":
                if (doc.selectedIndex >= 0) {
                    doc.options[doc.selectedIndex].selected = false;
                    doc.selectedIndex = 0;
                }
                break;
            case "select-multiple":
                while (doc.selectedIndex != -1) {
                    indx = doc.selectedIndex;
                    doc.options[indx].selected = false;
                }
                doc.selected = false;
                break;

            default:
                break;
        }
    }

}


//function emailCheck(emailStr)
//{
//    /* The following pattern is used to check if the entered e-mail address
//    fits the user@domain format.  It also is used to separate the username
//    from the domain. */

//    var emailPat = "/^(.+)@(.+)$/";
//    /* The following string represents the pattern for matching all special
//    characters.  We don't want to allow special characters in the address.
//    These characters include ( ) < > @ , ; : \ " . [ ] $ % &    */
//    var specialChars = "\\(\\)<>@,;:!·#$%&¬/=?¿¡*ºª\\\\_\\\"\\.\\[\\]";
//    /* The following string represents the range of characters allowed in a
//    username or domainname.  It really states which chars aren't allowed. */
//    var validChars = "[^\\s" + specialChars + "]";
//    /* The following pattern applies if the "user" is a quoted string (in
//    which case, there are no rules about which characters are allowed
//    and which aren't; anything goes).  E.g. "jiminy cricket"@disney.com
//    is a legal e-mail address. */
//    var quotedUser = "(\"[^\"]*\")";
//    /* The following pattern applies for domains that are IP addresses,
//    rather than symbolic names.  E.g. joe@[123.124.233.4] is a legal
//    e-mail address. NOTE: The square brackets are required. */
//    var ipDomainPat = "/^\"[(\"d{1,3})\".(\"d{1,3})\".(\"d{1,3})\".(\"d{1,3})\"]$/";
//    /* The following string represents an atom (basically a series of
//    non-special characters.) */
//    var atom = validChars + '+';
//    /* The following string represents one word in the typical username.
//    For example, in john.doe@somewhere.com, john and doe are words.
//    Basically, a word is either an atom or quoted string. */
//    var word = "(" + atom + "|" + quotedUser + ")";
//    // The following pattern describes the structure of the user
//    var userPat = new RegExp("^" + word + "(\\." + word + ")*$");
//    /* The following pattern describes the structure of a normal symbolic
//    domain, as opposed to ipDomainPat, shown above. */
//    var domainPat = new RegExp("^" + atom + "(\\." + atom + ")*$");
//    
//    /* Finally, let's start trying to figure out if the supplied address is
//    valid. */

//    /* Begin with the coarse pattern to simply break up user@domain into
//    different pieces that are easy to analyze. */
//    var matchArray = emailStr.match(emailPat);
//    if (matchArray == null) {
//        /* Too many/few @'s or something; basically, this address doesn't
//        even fit the general mould of a valid e-mail address. */
//        alarma("La dirección de correo parece inválida (comprueba @ y .).");
//        return false;
//    }
//    var user = matchArray[1];
//    var domain = matchArray[2];

//    // See if "user" is valid
//    if (user.match(userPat) == null) {
//        // user is not valid
//        alarma("El nombre de usuario no es válido..");
//        return false;
//    }

//    /* if the e-mail address is at an IP address (as opposed to a symbolic
//    host name) make sure the IP address is valid. */
//    var IPArray = domain.match(ipDomainPat);
//    if (IPArray != null) {
//        // this is an IP address
//        for (var i = 1; i <= 4; i++) {
//            if (IPArray[i] > 255) {
//                alarma("La dirección IP destino es inválida.");
//                return false;
//            }
//        }
//        return true;
//    }

//    // Domain is symbolic name
//    var domainArray = domain.match(domainPat);
//    if (domainArray == null) {
//        alarma("El dominio no parece ser válido.");
//        return false;
//    }

//    /* domain name seems valid, but now make sure that it ends in a
//    three-letter word (like com, edu, gov) or a two-letter word,
//    representing country (uk, nl), and that there's a hostname preceding
//    the domain or country. */

//    /* Now we need to break up the domain to get a count of how many atoms
//    it consists of. */
//    var atomPat = new RegExp(atom, "g");
//    var domArr = domain.match(atomPat);
//    var len = domArr.length;
//    if (domArr[domArr.length - 1].length < 2 ||
//    domArr[domArr.length - 1].length > 3) {
//        // the address must end in a two letter or three letter word.
//        alarma("La dirección debe acabar en un dominio de 3 letras (o de 2 letras en case de un pais).");
//        return false;
//    }

//    // Make sure there's a host name preceding the domain.
//    if (len < 2) {
//        var errStr = "Esta dirección carece de nombre de host.";
//        alarma(errStr);
//        return false;
//    }

//    // If we've gotten this far, everything's valid!
//    return true;
//}