function home_re(){
var f=document.form1;
  var usr_name=f.userid.value;
  var passwd=f.password.value;
  var name_str=new RegExp("^[a-zA-Z][a-zA-Z0-9_. ]+$","ig"); 
  var passwd_str=new RegExp("^[a-zA-Z0-9_@.]+$","ig");

  if(usr_name=='') 
  {
    alert("userid can't be blank");
    f.userid.select();
    return false; 
  } 

 if( usr_name=="User Name") 
  {
    alert("Please Enter a valid User Name");
    f.userid.select();
    return false; 
  } 
  if(!usr_name.match(name_str))
   {
     alert("It is not a Valid User Name.User name can contain character(a-z)(A-Z)(0-9)and (_. )It should start with a character."); 
	 f.userid.select();
     return false;    
   }
  
 if(usr_name.length<4)
  {
    alert("User Name should have atleast 4 characters and atmost 25 characters");
    f.userid.select(); 
    return false; 
  }
   
  if(usr_name.length>25)
  {
    alert("User Name should have atleast 4 characters and atmost 25 characters");
    f.userid.select(); 
    return false; 
  }

 if(passwd=='')
 {
   alert("Password can't be blank!");
   f.password.select();
    return false; 
 }

 if(passwd=="******")
 {
   alert("Please Enter Password");
   f.password.select();
    return false; 
 }
 
 if(!passwd.match(passwd_str))
 {
     alert("It is not a Valid Password .Password  can contain character(a-z)(A-Z)(0-9)and(_.@)It should start with a character."); 
   f.password.select();
     return false;    
   }

 if(passwd.length<6)
 {
  alert("Password should have atleast 6 characters and atmost 12 characters") ;
  f.password.select();
    return false;  
 }

  if(passwd.length>12)
 {
  alert("Password should have atleast 6 characters and atmost 12 characters") ;
  f.password.select();
  return false;  
 }else{
 document.form1.action="login.php";
 }
}