function show(obj){
 if(obj.type=="text"){
    obj.style.display="none";
    document.getElementById('UserPassword').style.display="block";
    document.getElementById('UserPassword').value="";
    document.getElementById('UserPassword').focus();
 }else{
    var UserPassword = document.getElementById('UserPassword').value;
    if(UserPassword.length<1){
      obj.style.display="none";
      document.getElementById('txt').style.display="block";
    }
 }
 }