errormessages.html

<script>

// this is a function that you're going to pass a messageCode to.
// the message code will be an integer and you'll return a string
// that is the error message.

function getErrorMessage(messageCode)
{
     var errorMessage = "";
     
     if(messageCode == 1)
          errorMessage = "Your username could not be found."
     } else if(messageCode == 2) {
          errorMessage = "Your password is incorrect."
     } else if(messageCode == 3) {
          errorMessage = "You are just an idiot."
     }

     return errorMessage;
}


// writes the 1st error message
document.write( getErrorMessage(1) );

// writes the 2nd error message
document.write( getErrorMessage(2) );

// writes the 3rd error message
document.write( getErrorMessage(3) );

// writes no error message
document.write( getErrorMessage(4) );


</script>