How can I hide the password entered via a JavaScript dialog prompt?

Question

How can I hide the password entered by a user in a dialog prompt in JavaScript? For example, using something like

var passwd = prompt(\"Enter Password : \",          


        

Answer 1

A solution to me, builded up with the help of the above and the tutorial from http://bluebirdjs.com/docs/async-dialogs.html was to use an async function. Because I wanted to replace the prompt and its logic. Unfortunately i could not find an easier solution, but this worked for me:

function passwordPrompt(text){
/*creates a password-prompt instead of a normal prompt*/
/* first the styling - could be made here or in a css-file. looks very silly now but its just a proof of concept so who cares */
var width=200;
var height=100;
var pwprompt = document.createElement("div"); //creates the div to be used as a prompt
pwprompt.id= "password_prompt"; //gives the prompt an id - not used in my example but good for styling with css-file
pwprompt.style.position = "fixed"; //make it fixed as we do not want to move it around
pwprompt.style.left = ((window.innerWidth / 2) - (width / 2)) + "px"; //let it apear in the middle of the page
pwprompt.style.top = ((window.innerWidth / 2) - (width / 2)) + "px"; //let it apear in the middle of the page
pwprompt.style.border = "1px solid black"; //give it a border
pwprompt.style.padding = "16px"; //give it some space
pwprompt.style.background = "white"; //give it some background so its not transparent
pwprompt.style.zIndex = 99999; //put it above everything else - just in case

var pwtext = document.createElement("div"); //create the div for the password-text
pwtext.innerHTML = text; //put inside the text
pwprompt.appendChild(pwtext); //append the text-div to the password-prompt
var pwinput = document.createElement("input"); //creates the password-input
pwinput.id = "password_id"; //give it some id - not really used in this example...
pwinput.type="password"; // makes the input of type password to not show plain-text
pwprompt.appendChild(pwinput); //append it to password-prompt
var pwokbutton = document.createElement("button"); //the ok button
pwokbutton.innerHTML = "ok";
var pwcancelb = document.createElement("button"); //the cancel-button
pwcancelb.innerHTML = "cancel";
pwprompt.appendChild(pwcancelb); //append cancel-button first
pwprompt.appendChild(pwokbutton); //append the ok-button
document.body.appendChild(pwprompt); //append the password-prompt so it gets visible
pwinput.focus(); //focus on the password-input-field so user does not need to click 

/*now comes the magic: create and return a promise*/
return new Promise(function(resolve, reject) {
    pwprompt.addEventListener('click', function handleButtonClicks(e) { //lets handle the buttons
      if (e.target.tagName !== 'BUTTON') { return; } //nothing to do - user clicked somewhere else
      pwprompt.removeEventListener('click', handleButtonClicks); //removes eventhandler on cancel or ok
      if (e.target === pwokbutton) { //click on ok-button
        resolve(pwinput.value); //return the value of the password
      } else {
        reject(new Error('User cancelled')); //return an error
      }
      document.body.removeChild(pwprompt);  //as we are done clean up by removing the password-prompt

    });
    pwinput.addEventListener('keyup',function handleEnter(e){ //users dont like to click on buttons
        if(e.keyCode == 13){ //if user enters "enter"-key on password-field
            resolve(pwinput.value); //return password-value
            document.body.removeChild(pwprompt); //clean up by removing the password-prompt
        }else if(e.keyCode==27){ //user enters "Escape" on password-field
            document.body.removeChild(pwprompt); //clean up the password-prompt
            reject(new Error("User cancelled")); //return an error
        }
    });
}); 
}

now with this you can use the await inside an async-function to get nearly the same result as the window.prompt():

async function testThePrompt(){
  var result = await passwordPrompt("please enter your password");
  alert(result);
}

you see that this code nearly looks like the use of the old "prompt". The big difference is that we now use async-code - so the code does not stop executing while waiting for the password - just your async-function will wait till the password is either entered or . but for me it helped a lot to not rewrite my whole code anew just to handle the callback-function and stuff. note that this only works in browsers which supports async, so from 2017 onward. old browsers like on older ipads or older versions of ios in general it will not work. if you want to check for the event the user did not enter anything use

async function testThePrompt(){
  var result;
  try{
    result = await passwordPrompt("please enter your password");
    alert(result);
  } catch(e){
    alert("user canceled");
  }
}