insert new value into listbox from textarea

Quote syah:

i had create 3 list box
1. country
2. subcountry
3.city
but the problm is, how the user want to insert new record in listbox city?
i had create one text area beside the city's listbox..,so user can choice either they want to add a new city....at the same time the record will automatic entered in city record and restaurant record where i put city_id in restaurant table...

Quote melvyn:

You need javascript. Some custom php and some understanding of how this work.

  
function toggleTextBox(cityname){  
  if(cityname == 'other'){  
    document.forms['0'].city_textbox.display = 'block'  
  }else{  
    document.forms['0'].city_textbox.display = 'none'  
  }  
}  

  
// first let's check if the user entered a custom city  
if(strlen($Container->city_textbox->GetValue()) >0 ){  
  $db = new clsDBMydatabase();  
  $custom_city = $Container->city_textbox->GetValue();  
  $SQL = "INSERT INTO city (city_field) VALUES ('$custom_city') ";  
  $db->query($SQL);  
    
  // now let's find the last inserted id you need:  
  $SQL = "SELECT id FROM city WHERE city_field = '$custom_city'";  
  $db->query($SQL);  
  $city_id = $db->f(0); // now we have the id to the current city.  
   
  $Container->city_listbox->SetValue($city_id);  
    
}else{  
// do nothing  
}  

Quote :

The value in field s_city is not valid.

Quote syah:

i have already done as u wrote before to insert the new from the textbox and it insert into TABLE city. hoe i want insert the value into TABLE restaurant that call the last id from TABLE city?

  
// now let's find the last inserted id you need:    
  $SQL = "SELECT id FROM city WHERE city_field = '$custom_city'";    
  $db->query($SQL);    
  $city_id = $db->f(0); // now we have the id to the current city.    

  
while ($db->next_record())  
{  
$SQL = "INSERT INTO restaurant (city_id) VALUES (" . $db2->ToSQL($city_id,ccsInteger).")";  
$db2->query($SQL);  
}  

  
$SQL = "INSERT INTO restaurant (city_id) VALUES ";  
while ($db->next_record())  
{  
$SQL .= "(" . $db2->ToSQL($city_id,ccsInteger).")";  
}  
  
$db2->query($SQL);