// JavaScript Document
function check_membership() {

msg = "",  error = false;

if(document.membership.name.value=="") {
error = true;
msg+="- Name of company is required!\n";
}
if(document.membership.address.value=="") {
error = true;
msg+="- Address is required!\n";
}
if(document.membership.tel.value=="") {
error = true;
msg+="- Telephone is required!\n";
}
if(document.membership.email.value!="") {
error_email = false;
email_addr = document.membership.email.value;
index_at = email_addr.indexOf("@");
if (index_at == -1 || index_at == 0 || index_at == email_addr.length-1 || email_addr.indexOf("@", index_at+1) != -1) error_email = true;
else if ((email_addr.length-1 == email_addr.lastIndexOf(".")) || email_addr.indexOf(".", index_at) == -1) error_email = true;
if (error_email) {error = true; msg += "- E-mail address must be valid\n";}
}
if(document.membership.contact.value=="") {
error = true;
msg+="- Name of representative is required!\n";
}
if(document.membership.designation.value=="") {
error = true;
msg+="- Designation is required!\n";
}
if (error) {alert(msg);return false;} else return true; }


function opencontact(targ,selObj,restore){ //v3.0
  if(selObj.options[selObj.selectedIndex].value != "") {
    eval(targ+".location.replace('"+selObj.options[selObj.selectedIndex].value+"')");
    if (restore) selObj.selectedIndex=0;
  }
}

function DoViewIFRAME(v1,v2,v3) {
document.getElementById(v1).style.display = "none";
document.getElementById(v2).style.display = "";
document.getElementById(v3).style.display = "";
}
function DoHideIFRAME(v1,v2,v3) {
document.getElementById(v1).style.display = "none";
document.getElementById(v2).style.display = "none";
document.getElementById(v3).style.display = "";
}

<!--
function toggle(theDiv) {
     var elem = document.getElementById(theDiv);
     elem.style.display = (elem.style.display == "none")?"":"none";
}
//-->