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Animate array from user input like typewriter (javascript)

I suppose my question is a bit similar to this one, but I can't really work out how to do my specific need from it. I'm building a very basic text adventure, and I'd like the returned text - after the user has entered a command - to be returned in a typewriter style. Here's a snippet of my commands so far (there'll be a lot more, I don't mind that this will be built in a bit of a tedious way)
<script>
textIn = document.getElementById("input-textbox");
textOut = document.getElementById("output-textbox");
function process(input) {
if (input == "hi") { textOut.innerHTML += "Hello to you too!<br><br>"; }
else if (input == "exit") { textOut.innerHTML += "No."; }
}
function go() {
var input = textIn.value;
textIn.value = "";
var output = process(input);
textOut.value += output + "\n";
}
</script>
and the HTML
<div id="output-textbox">
Returned text goes here.
</div>
<form onSubmit="go();return false;">
<input id="input-textbox" name="command" value="" autofocus="autofocus"/>
</form>
Thank you so much for your help in advance! This solution doesn't need to be beautiful, code wise, nor very nifty. It just has to work, I have no standards at all with this!

Based on William B's answer, here is a more condensed version:
https://jsfiddle.net/sators/4wra3y1p/1/
HTML
<div id="output-typewriter"></div>
Javascript
function typewriterText(text) {
var outEl = document.querySelector('#output-typewriter');
var interval = 50; // ms between characters appearing
outEl.innerHTML = '';
text.split('').forEach(function(char, i){
setTimeout(function () {
outEl.innerHTML += char;
}, i * interval);
});
}
typewriterText('this is an example');

Create a timeout for each character inside a loop, with each timeout being a bit later than the last. See: https://jsfiddle.net/fswam77j/1/
var outputEl = document.querySelector('#output-textbox');
var charInterval = 50; // ms between characters appearing
function showOutput(text) {
outputEl.innerHTML = '';
for(var i = 0; i < text.length; i++) {
showChar(text, i);
}
}
function showChar(text, i) {
setTimeout(function () {
outputEl.innerHTML += text[i];
}, i * charInterval);
}
showOutput('this is an example');
process the input:
function process(input) {
if (input == "hi") {
showOutput("Hello to you too!");
}
else if (input == "exit") {
showOutput("No.");
}
}

Javascript: selecting values from a dropdown

I had a standard calculation javascript and now I need to add-in multiple calculations based on a user-selected value - can't seem to get it to work....! Any chance someone could have a look and tell me where I'm going wrong???
<script type="text/javascript">
function calculate() {
var noPeople = document.ContactForm.noPeople.value;
var ddl = document.getElementById("menuType");
var selectedValue = ddl.options[ddl.selectedIndex].value;
var noPeople_excess = (noPeople-6);
if (selectedValue == 3) {
var basic = 337;
var marchCost = (50*noPeople);
if (marchCost <= basic) {
document.ContactForm.marchCost.value = 337;
document.ContactForm.marchCostVin.value = basic +(noPeople*25)
} else {
document.ContactForm.marchCost.value = basic +(noPeople_excess*34);
document.ContactForm.marchCostVin.value = basic +(noPeople_excess*34)+(noPeople*25)
}
} else (selectedValue == 4) {
var basic = 368;
var marchCost = (55*noPeople);
if (marchCost <= basic) {
document.ContactForm.marchCost.value = 368;
document.ContactForm.marchCostVin.value = basic +(noPeople*25)
} else {
document.ContactForm.marchCost.value = basic +(noPeople_excess*44);
document.ContactForm.marchCostVin.value = basic +(noPeople_excess*44)+(noPeople*25)
}
} else (selectedValue == 5) {
var basic = 419;
var marchCost = (60*noPeople);
if (marchCost <= basic) {
document.ContactForm.marchCost.value = 419;
document.ContactForm.marchCostVin.value = basic +(noPeople*25)
} else {
document.ContactForm.marchCost.value = basic +(noPeople_excess*54);
document.ContactForm.marchCostVin.value = basic +(noPeople_excess*54)+(noPeople*25)
}
}
}
</script>

This question was indeed many times answered, however here is a simple solution for you:
//get select value and assing to an input element
function setValue(selectId, elemId) {
var thisID = selectId,
valueSelected = document.getElementById(thisID).value
console.log(thisID + ' has value of ' + valueSelected);
document.getElementById(elemId).value = valueSelected;
}
http://plnkr.co/edit/rnenKVaNcJ9RhqLzUaWi
regards.

I might be confused about the two DDLs, but either the selected value should be the selectedIndex to compare with integers:
var selectedValue = ddl.selectedIndex;
or the conditions should be checking strings:
if (selectedValue == "3"){

your elses are missing an if.. eg: else if (selectedvalue==4)
I suggest using switch(selectedvalue) { case 3: ... break; case 4: ...etc
would be easier to read in this case, especially if you add more options.

how to chang the style property in javascript?

I want to change a picture in my site every 5 second and I have used this code!but it does'n work!
where is the problem!
<script type="text/javascript"src="http://code.jquery.com/jquery-1.9.1.min.js"> </script>
<script type="text/javascript">
$(document).ready(function () {
var interval = setInterval(time, 5000);
}); // ending ')' was missing
</script>
<script type="text/javascript">
function time() {
var m11 = document.getElementById("m1");
var m22 = document.getElementById("m2");
var m33 = document.getElementById("m3");
var name= mm11.style.display.toString();
if ( name=="block") {
m11.style.display = "none";
m22.style.display = "block";
}
if(m22.style.display.toString() ="block") {
m22.style.display = "none";
m11.style.display = "block";
}
}
</script>

Change
if(m22.style.display.toString() ="block")
with
if(m22.style.display.toString() == "block")
Also, you don't need the "toString()", because display is already a string.
Here is a shorter code:
function time() {
var m11 = document.getElementById("m1");
var m22 = document.getElementById("m2");
var m33 = document.getElementById("m3");
if (m11.style.display == "block") {
m11.style.display = "none";
m22.style.display = "block";
}
if(m22.style.display == "block") {
m22.style.display = "none";
m11.style.display = "block";
}
}

Since you're already using jquery It seems to me that you can simply use
function time() {
$('#m1').toggle();
$('#m2').toggle();
}

You can directly use. Note that it should be == when comparing in If statement
document.getElementById('m1').style.display = 'none';

On the second if block, you miss-typed the comaprsion operator.
if(m22.style.display.toString() ="block")
Should be
if(m22.style.display.toString() =="block")

Better way is as follows:
HTML:
<div id="m1" style="display:block">Hello1</div>
<div id="m2" style="display:none">Hello2</div>
JS:
setInterval(time, 5000);
function time() {
$("#m1, #m2").toggle();
}
Refer LIVE DEMO
UPDATED:
As per #Sarah sh comment, you need to show images one by one.
Here is your functionality.
HTML:
<div class="img">Hello1</div>
<div class="img">Hello2</div>
<div class="img">Hello3</div>
<div class="img">Hello4</div>
JS:
var currObj = $(".img").first();
$(currObj).show();
$(".img").not(currObj).hide();
setInterval(rotateImage, 2000);
function rotateImage() {
var tempObj = currObj;
if ($(tempObj).is(":last"))
currObj = $(".img").first();
else
currObj = $(currObj).next();
$(tempObj).hide();
$(currObj).show();
}
Refer LIVE DEMO

Taking var with JS prompt - how can I make it through HTML form?

I've been learning HTML/CSS/JavaScript for a couple of weeks now, and I am currently practicing on a mini project, which consists of letting people answer math questions, and validating their answers.
My current progress can be seen at http://dany.faceflow.com
I know I am probably not using the best strategy to develop this mini game, so any advice would be useful on that. However right now, the problem is that I am taking the user answer with a variable through JS prompt, and I want to do it via an HTML form (less annoying).
In my source code you can see this line within the function:
var userInput = prompt(numb1 + symbol + numb2);
Then, still in the same function, I have an if/else structure to compare the user's answer with the right answer. The code works, I just don't know how to make the prompt HTML-based instead. I've tried an html form with an ID and in the JS using getElementById, document.write and some other stuff but I never got it to work for that part.
(Here's all the JS)
var number1 = function() {
var numb1 = Math.floor(Math.random() * 41) + 10;
return numb1;
}
var number2 = function() {
var numb2 = Math.floor(Math.random() * 41) + 10;
return numb2;
}
var userAnswer = function() {
var numb1 = number1();
var numb2 = number2();
var randomSymbol = Math.random();
if (randomSymbol > 0.5) {
var symbol = "+";
} else {
var symbol = "-";
}
// add the math question in the html bubble
document.getElementById('bubble').innerHTML = numb1 + symbol + numb2;
// Prompts the user to give an answer. Change this to HTML.
var userInput = prompt(numb1 + symbol + numb2);
//var userInput = document.getElementById('tw').value;
if (symbol == "+" && userInput == (numb1 + numb2)) {
document.getElementById('feedback').innerHTML = "Congratulations!";
} else if (symbol == "+" && userInput !== (numb1 + numb2)) {
document.getElementById('feedback').innerHTML = "Wrong!";
} else if (symbol == "-" && userInput == (numb1 - numb2)) {
document.getElementById('feedback').innerHTML = "Congratulations!";
} else if (symbol == "-" && userInput !== (numb1 - numb2)) {
document.getElementById('feedback').innerHTML = "Wrong!";
} else {
alert("Something wrong happened. Try again.");
}
return userInput;
}
(The HTML)
<!DOCTYPE html>
<html>
<head>
<link type="text/css" rel="stylesheet" href="css/stylesheet.css" />
<script src="js/script.js"></script>
<title>Improve Your Math Skills!</title>
</head>
<body>
<center>
<button onclick="userAnswer()">PLAY NOW!</button>
<div id="bubble"></div>
<div id="feedback"></div>
<!-- <script src="http://code.jquery.com/jquery-1.9.1.min.js"></script> -->
</center>
</body>
</html>
Thank you

You can use an input tag instead of the prompt. Change the HTML just as in Dinesh's answer;
<div id="bubble"></div>
<div id="inp" style="display: none;">
<input type="text" id="ans"></input> <button id="subBtn">Submit</button>
</div>
<div id="feedback"></div>
Now, for the JavaScript, there a few things to consider. Firstly, you have
var number1 = function() {
var numb1 = Math.floor(Math.random() * 41) + 10;
return numb1;
}
var number2 = function() {
var numb2 = Math.floor(Math.random() * 41) + 10;
return numb2;
}
Both functions do exactly the same thing; you don't need two separate functions to get two separate random numbers. So, only one function will suffice.
var number = function() {
return Math.floor(Math.random() * 41) + 10;
};
Secondly, now we have two functions. userAnswer to post a new question when 'Play Now!' is clicked and, say, evalAnswer to evaluate the answer written in the input field when 'Submit' is clicked.
In userAnswer, you generate two new random numbers and figure out which operation will be conducted on them. At this point, you can simply evaluate the answer yourself and store it in a global variable. This makes things easier when you evaluate the answer, you only need to do a simple comparison.
Other than that, you update innerHTML for bubble and display the div inp.
In evalAnswer, you get the value from ans and compare it with the previously computed value of the current answer, and then accordingly update feedback.innerHTML.
Here's the code;
//variable to maintain the current answer
var curAns = 0;
//Here, I get all the DOMElements I will use
var playBtn = document.getElementById('playBtn');
var bubble = document.getElementById('bubble');
var inp = document.getElementById('inp');
var ans = document.getElementById('ans');
var subBtn = document.getElementById('subBtn');
var feedback = document.getElementById('feedback');
//I add the event listeners
//This is equivalent to using 'onclick'
//in the HTML, and doing it this way is only
//my personal preference
playBtn.addEventListener('click', function() {userAnswer();}, false);
subBtn.addEventListener('click', function() {evalAnswer();}, false);
//Function to get random number
var number = function() {
return Math.floor(Math.random() * 41) + 10;
};
//This function will be executed when 'Play Now!' is clicked.
var userAnswer = function() {
//Get two separate random numbers in
//numb1 and numb2
var numb1 = number();
var numb2 = number();
var symbol = '';
var randomSymbol = Math.random();
//Determine the operation to be used
//and compute the corresponding correct answer for the current
//question
if (randomSymbol > 0.5) {
symbol = "+";
curAns = numb1+numb2;
} else {
symbol = "-";
curAns = numb1-numb2;
}
//Add math question to bubble
bubble.innerHTML = 'What is ' + numb1 + ' ' + symbol + ' ' + numb2 + '?';
feedback.innerHTML = '';
//Make inp div visible
inp.style.display = 'block';
//Reset input value to ''
ans.value = '';
};
//This function will be executed when 'Submit' is clicked
var evalAnswer = function() {
//Simply compare input value with computed
//answer and update feedback
if(parseInt(ans.value) !== curAns) {
feedback.innerHTML = 'Wrong answer, try again!';
}
else {
feedback.innerHTML = 'You got it right, congratulations!';
}
};
Here's a working example.
Hope that helped!

What I understand from your question is that you need the same functionality in HTML itself rather than driven by JS in a prompt box, if so,the below additions to your code should help:
HTML adition:
<div id="bubble"></div>
<div id="check_ans_div" style="display:none;">
<input type="text" id="txt_answer" />
<input type="submit" value="Check Answer" onclick="checkanswer()" />
</div>
<div id="feedback"></div>
JS changes:
var number1 = function() {
var numbx = Math.floor(Math.random() * 41) + 10;
return numbx;
}
var number2 = function() {
var numby = Math.floor(Math.random() * 41) + 10;
return numby;
}
var numb1=0; var numb2=0;
var userAnswer = function() {
numb1 = number1();
numb2 = number2();
var randomSymbol = Math.random();
if (randomSymbol > 0.5) {
var symbol = "+";
} else {
var symbol = "-";
}
// add the math question in the html bubble
document.getElementById('bubble').innerHTML = numb1 + symbol + numb2;
if(document.getElementById('check_ans_div').style.display=='none')
document.getElementById('check_ans_div').style.display='block';
document.getElementById('txt_answer').value='';
}
function checkanswer(){
var userInput= document.getElementById('txt_answer').value;
if (symbol == "+" && userInput == (numb1 + numb2)) {
document.getElementById('feedback').innerHTML = "Congratulations!";
} else if (symbol == "+" && userInput !== (numb1 + numb2)) {
document.getElementById('feedback').innerHTML = "Wrong!";
} else if (symbol == "-" && userInput == (numb1 - numb2)) {
document.getElementById('feedback').innerHTML = "Congratulations!";
} else if (symbol == "-" && userInput !== (numb1 - numb2)) {
document.getElementById('feedback').innerHTML = "Wrong!";
} else {
alert("Something wrong happened. Try again.");
}
}

Change number input to characters

I built this simple script to input a certain number,
Now I want to use this but with characters, how would I change the Num == input and what would I change it to?
Many Thanks
<script type="text/javascript">
function check_number()
{
var num = document.getElementById('input_number').value;
if (num == smaller){
document.getElementById('result_image_correct').style.display = 'block';
document.getElementById('result_image_incorrect').style.display = 'none';
document.getElementById('result_image_correct2').style.display = 'block';
}
else{
document.getElementById('result_image_incorrect').style.display = 'block';
document.getElementById('result_image_correct').style.display = 'none';
}
}
</script>

Then just change smaller to "smaller" or 'smaller'.