Dynamically create controls in Javascript.

function Confirm() 
{
     var confirm_value = document.createElement("INPUT");
     confirm_value.type = "hidden";
     confirm_value.name = "confirm_value";

     if (confirm("Do you want to save data?"))
     {
          confirm_value.value = "Yes";
     } 
     else 
     {
          confirm_value.value = "No";
     }
     
    document.forms[0].appendChild(confirm_value);
}