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Check the login

importance: 3

Write the code which asks for a login with prompt.

If the visitor enters "Admin", then prompt for a password, if the input is an empty line or Esc – show “Canceled”, if it’s another string – then show “I don’t know you”.

The password is checked as follows:

  • If it equals “TheMaster”, then show “Welcome!”,
  • Another string – show “Wrong password”,
  • For an empty string or cancelled input, show “Canceled”

The schema:

Please use nested if blocks. Mind the overall readability of the code.

Hint: passing an empty input to a prompt returns an empty string ''. Pressing ESC during a prompt returns null.

Run the demo

let userName = prompt("Who's there?", '');

if (userName === 'Admin') {

  let pass = prompt('Password?', '');

  if (pass === 'TheMaster') {
    alert( 'Welcome!' );
  } else if (pass === '' || pass === null) {
    alert( 'Canceled' );
  } else {
    alert( 'Wrong password' );

} else if (userName === '' || userName === null) {
  alert( 'Canceled' );
} else {
  alert( "I don't know you" );

Note the vertical indents inside the if blocks. They are technically not required, but make the code more readable.