一個註冊驗證的JavaScript

function checkUserReg(action)
{if(action=="add"){
if(document.UserRegister.username.value=="")
 {
  document.UserRegister.username.focus();
  alert("對不起，請輸入您的使用者名稱！");
  return false;
  
 }
if(document.UserRegister.username.value.length<4)
 {
  document.UserRegister.username.focus();
  alert("對不起,使用者名稱應在4個或4個字元以上，請重新輸入！");
  return false;
  
 }

if(document.UserRegister.password.value=="")
 {
  document.UserRegister.password.focus();
  alert("對不起，請輸入您的使用者密碼！");
  return false;
  
 }
if(document.UserRegister.password.value.length<6)
 {
  document.UserRegister.password.focus();
  alert("對不起，密碼應在6個字元以上，請重新輸入！");
  return false;
  
 }

if(document.UserRegister.repassword.value=="")
 {
  document.UserRegister.repassword.focus();
  alert("對不起，請輸入確定密碼！");
  return false;
  
 } 

if(document.UserRegister.repassword.value!=document.UserRegister.password.value)
       {
         document.UserRegister.password.focus();
         alert("對不起，兩次輸入的密碼不一樣，請重新輸入！");
         document.UserRegister.password.value="";
         document.UserRegister.repassword.value="";
         return false;
        }

if(document.UserRegister.zsname.value=="")
        {document.UserRegister.zsname.focus();
         alert("對不起,請輸入真實姓名！");
         return false;
         }

if(document.UserRegister.telephone.value=="")
{document.UserRegister.telephone.focus();
alert("對不起,請輸入聯絡電話！");
 return false;
}

var tel = "0123456789";
for (i=0; i< document.UserRegister.telephone.value.length; i++)
{
 
var CheckChar = document.UserRegister.telephone.value.charAt(i);
if (tel.indexOf(CheckChar) == -1||document.UserRegister.telephone.value.length<10||document.UserRegister.telephone.value.length>12)
{
 alert("對不起，請輸入正確的電話號碼！");
 document.UserRegister.telephone.focus();
 return false;
 
}
}

 

 

if(document.UserRegister.email.value==""){
document.UserRegister.email.focus(); 
alert("對不起,請輸入Email");
  return false;

}

if(document.UserRegister.email.value.charAt(0)=="." ||       
         document.UserRegister.email.value.charAt(0)=="@"||      
         document.UserRegister.email.value.indexOf('@', 0) == -1 ||
         document.UserRegister.email.value.indexOf('.', 0) == -1 ||
         document.UserRegister.email.value.lastIndexOf("@")
==document.UserRegister.email.value.length-1 ||document.UserRegister.email.value.lastIndexOf(".")
==document.UserRegister.email.value.length-1
){document.UserRegister.email.focus();
  alert("對不起,請輸入正確Email");
  return false;

}

if(document.UserRegister.address.value==""){
document.UserRegister.address.focus(); 
alert("對不起,請輸入郵寄地址");
  return false;

}

if(document.UserRegister.zipcode.value==""){
document.UserRegister.zipcode.focus(); 
alert("對不起,請輸入郵遞區號");
  return false;

}

var youpian = "0123456789";
for (i=0; i< document.UserRegister.zipcode.value.length; i++)
{
 
var CheckChar = document.UserRegister.zipcode.value.charAt(i);
if (youpian .indexOf(CheckChar) == -1||document.UserRegister.zipcode.value.length!=6)
{
 alert("對不起，請輸入正確的郵遞區號！");
 document.UserRegister.zipcode.focus();
 return false;
 
}

if(document.UserRegister.idcard.value==""){
document.UserRegister.idcard.focus(); 
alert("對不起,請輸入信用卡號");
  return false;

}

var idca = "0123456789";
for (i=0; i< document.UserRegister.idcard.value.length; i++)
{
 
var CheckChar = document.UserRegister.idcard.value.charAt(i);
if (idca.indexOf(CheckChar) == -1||document.UserRegister.idcard.value.length!=16)
{
 alert("對不起，請輸入正確的信用卡號！");
 document.UserRegister.idcard.focus();
 return false;
 
}
}
}document.all.item("action").value=action;
        document.UserRegister.submit();
    }}