function f_Disable(obj) {

    var v = document.getElementById('a' + obj);
    if (!v) return;
    var e = document.getElementById(obj);
    if (!e) return;
    
    e.disabled = v.selectedIndex==0;
    
}

function maxLengthPaste(field, maxChars) {
    event.returnValue = false;
    if ((field.value.length + window.clipboardData.getData("Text").length) > maxChars) {
        return false;
    }
    event.returnValue = true;
}


 function f_ValidateNewsLetter(){
 
    var m;
    
    var v1=document.getElementById('fid_newsletteremail').value;
    
    if(!v1) m='The field Email is mandatory.';
    else if(!f_CheckEmail(v1)) m='The field Email is invalid.';
        
    if(m){
        alert(m);
        return false;
    }
    
    return true;
}
 function f_ValidatePayPal(){
 
    var m;
    
    var v1=document.getElementById('fid_nome').value;
    var v2=document.getElementById('fid_email').value;
    var v3=document.getElementById('fid_titolo').value;
    
    if(!v1) m='The field Name is mandatory.';
    else if(!v2) m='The field Email is mandatory.';    
    else if(!f_CheckEmail(v2)) m='The field Email is invalid.';
    else if(!v3) m='The field Title is mandatory..';
        
    if(m){
        alert(m);
        return false;
    }
    
    document.getElementById('fid_description').value='Quota iscrizione Cortopotere 2008 per ' + v1 + ' [' + v2 + '] "' + v3 + '"';
    return true;
}
function f_CheckEmail(email) 
{
    var valid = "y";

    if (email != "") {

        if (email.length<7 || email.indexOf("@.") != -1 || email.indexOf("-.") != -1 || email.indexOf("_.") != -1 ||

                email.indexOf("..") != -1 || email.indexOf("._") != -1 || email.indexOf(".-") != -1 || 

                email.indexOf(".@") != -1 || email.indexOf("@-") != -1 || email.indexOf("@_") != -1 ||

                email.indexOf("@") != email.lastIndexOf("@") || email.indexOf("@") == -1 || email.indexOf(".") == -1 ||

                (email.length - (email.lastIndexOf(".") + 1)) < 2) 

            return false;

        else {

            a = "abcdefghijklmnopqrstuvwxyz0123456789@-_.";

            b = 0;

            while (b < email.length) {

                if (a.indexOf(email.charAt(b)) == -1) return false;

                b = b + 1;

            }

        }

    }

    rx = /^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.[a-z][a-z]$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.aero$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.biz$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.coop$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.com$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.edu$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.gov$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.info$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.int$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.mil$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.museum$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.name$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.net$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.org$|^[a-z0-9\._]*[a-z0-9_]@[a-z0-9][a-z0-9\-\.]*[a-z0-9]\.pro$/i;

    if (rx.test(email)) {

        rx = /^[a-z0-9_]/i;

        if((rx.test(email))) return true;

    }

    

    return false;

}