I just want to get the nodes's render time when I insert 100000 nodes into document,I had tried few ways,but result unexpected.
Here is the example:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>node insert cost time test</title>
<script>
var st = Date.now();
</script>
</head>
<body>
<h1>Placehoder</h1>
<h1 id="h1"></h1>
<h1 id="h2"></h1>
<h1 id="h3"></h1>
<h1 id="h4"></h1>
<h1 id="h5"></h1>
<div id="box"></div>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script>
var en = Date.now();
$("#h4").html("White cost time:" + (en - st));
</script>
<script>
let data = [];
for(let i =0;i<100000;i++){
data.push({
name:"test",
age:18,
gender:"female"
})
}
const s = Date.now();
let list = data;
const timer = setInterval(() => {
const ss = Date.now();
if ($("#indexid-" + (list.length - 1)).size() > 0) {
const findTime = new Date();
const ft = + findTime;
$("#h5").html(findTime)
$("#h1").html(`The RealTime is ${findTime - s}`)
clearInterval(timer);
}
}, 1)
const tpl = '<div id="indexid-{id}">' +
'<h2>Name：{name}</h2>' +
'<h4>Gender：{gender}</h4>' +
'<h6>Age：{age}</h6>' +
'</div>'
let res = [];
list.forEach((item, index) => {
item.id = index;
let str = tpl.replace(/\{(\w+)\}/gi, function ($, $1) {
if (item[$1] + "") {
return item[$1];
}
return ""
})
res.push(str);
})
//insert 100000 nodes into document
//then get the nodes render time
$("#box").html(res.join(""))
const e = Date.now();
$("#h2").html(`JS execute time：${e - s}ms`)
</script>
</body>
</html>
This works well on desktop browsers,but not on the mobileweb.
On mobile web,the output time is smaller than what it should be.I also used MutationObserver Api,but got the same result,could anyone help me?
Related
i am truly new with programing with javaScript so i just start to learn it, it will be good you are going to reply using a simple js code
my code does'nt stop when i press stop i want to clear the interval that i named with myTimer if i didn't put setInterval inside the function it just work directly and if there is any way to make my code more short please mentiot it.
const // my variable
myHour = document.getElementById("hours"),
myMin = document.getElementById("min"),
mySecond = document.getElementById("second"),
myMiliSecond = document.getElementById("dsecond"),
startchrono = document.getElementById("start"),
getLap = document.getElementById("lap"),
stopchrono = document.getElementById("stop"),
resetchrono = document.getElementById("reset"),
result = document.getElementById("result");
let // variable
milisecond = 0,
second = 0,
minute = 0,
hour = 0,
chronoRun = false,
round = 0;
function decoration(item) // this function is for add 0 if second or minute less than 10
{
if (String(item).length < 2) {
item = "0" + item;
}
return item;
}
function lapset() // function that create a new row in the table to save rounds
{
round++;
let // decoration add 0 if number under 10
ds = decoration(milisecond),
s = decoration(second),
m = decoration(minute),
h = decoration(hour);
if (round <= 10) {
const // insert the row in table
tr = result.insertRow(-1);
tr.insertCell(0).innerHTML = round;
tr.insertCell(-1).innerHTML = h + ":" + m + ":" + s + ":" + ds;
} else if (round <= 11) {
tr = result.insertRow(-1);
tr.insertCell(-0).innerHTML = "-";
tr.insertCell(-1).innerHTML = "you can't add any more laps";
getLap.setAttribute("disabled", "true");
}
}
function chrono() //chrono start
{
// chrono
milisecond++;
// make sure that minute, second have to be less than 60
if (milisecond > 10) {
milisecond = 0;
second++;
}
if (second > 59) {
second = 0;
minute++;
}
if (minute > 59) {
minute = 0;
hour++;
}
let // decoration add 0 if number under 10
ds = decoration(milisecond),
s = decoration(second),
m = decoration(minute),
h = decoration(hour);
myMiliSecond.innerHTML = ds;
mySecond.innerHTML = s;
myMin.innerHTML = m;
myHour.innerHTML = h;
startchrono.setAttribute("disabled", "true");
}
// function chronoStarts() {}
const myTimer = () => {
setInterval(chrono, 100);
};
const test = () => {
return clearInterval(myTimer);
};
startchrono.addEventListener("click", myTimer);
getLap.addEventListener("click", lapset);
stopchrono.addEventListener("click", test);
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Document</title>
</head>
<body>
<div id="chrono">
<div id="timer">
<span id="hours" class="time">00</span>
<span class="sep">:</span>
<span id="min" class="time">00</span>
<span class="sep">:</span>
<span id="second" class="time">00</span>
<span class="sep">:</span>
<span id="dsecond" class="time">00</span>
</div>
<div id="btnarea">
<button id="start" class="btnevent">start</button>
<button id="lap" class="btnevent">lap</button>
<button id="stop" class="btnevent">stop</button>
<button id="reset" class="btnevent">reset</button>
</div>
<table id="result">
<caption>saved lap</caption>
<tbody>
<tr>
<th class="round">round</th>
<th class="laptime">time</th>
</tr>
</tbody>
</table>
</div>
<script src="newpagescript.js"></script>
</body>
</html>
and that is my html code i think every is ok with my code but if there any issue i am looking for adives
You need to get the return value of the setInterval function and then pass that value as a parameter in the clearInterval function. For example, see below:
`// function chronoStarts() {}
let intervalId = 0;
const myTimer = () => {intervalId = setInterval(chrono, 100);};
const test = () => {
clearInterval(intervalId);
};
startchrono.addEventListener("click", myTimer);
getLap.addEventListener("click", lapset);
stopchrono.addEventListener("click", test);`
How can I fix the function to delete all todoItems? My guess is that the for loops is not working right :\ I appreciate any help with my problem! I have only 1-month of experience with javascript.
How can I fix the function to delete all todoItems? My guess is that the for loops is not working right :\ I appreciate any help with my problem! I have only 1-month of experience with javascript.
function selectColorStatus(event){
let target = event.target;
target.classList.toggle('todoTextSelected');
}
function createToDoItem(userInputValue){
// To-Do Item Container
let todoItem = document.createElement("div");
todoItem.classList.add("row", "flx");
todoItem.onclick = selectColorStatus;
// Clear List
let btnDeleteItem = document.getElementById('btnDeleteItem');
btnDeleteItem.onclick = function (){
for(let i = 0; i < todoItem; i++){
todoItem.remove();
}
}
// Inner Text
let todoText = document.createElement('div');
todoText.classList.add('grow');
todoText.innerText = userInputValue;
// Date
let CreateDate = document.createElement('div');
CreateDate.classList.add('date');
let date = new Date();
year = date.getFullYear();
month = date.getMonth();
day = date.getDay();
CreateDate.innerText = 'Created at ' + year + '-' + month + '-'+ day;
// Delete Button
let deleteBtn = document.createElement('div');
deleteBtn.classList.add('btnDelete');
deleteBtn.innerText = 'X';
deleteBtn.onclick = function(){
todoItem.remove();
}
todoItem.appendChild(todoText);
todoItem.appendChild(CreateDate)
todoItem.appendChild(deleteBtn);
let todoItemsContainer = document.getElementById('todoItemsContainer');
todoItemsContainer.appendChild(todoItem);
}
// Item Entry and Validation
function ToDoItemHandler(){
let userInput = document.getElementById('toDoEntry');
let userInputValue = userInput.value;
if(userInputValue == ''){
alert('Entry can not be empty!')
}else{
createToDoItem(userInputValue);
userInput.value = '';
}
}
// Add Item Button
let btnAddItem = document.getElementById('btnAddItem');
btnAddItem.onclick = ToDoItemHandler;
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<link href = './style/style.css' rel='stylesheet'>
<title>To-Do-List</title>
</head>
<body>
<div id = 'container'>
<div id="toDoHeader">
<h1>To-Do List</h1>
<div id = 'toDoContent'>
<input type = 'text' id = 'toDoEntry' name = 'toDoEntry' placeholder = 'Add item here'>
<button type = 'button' id = 'btnAddItem' name = 'addToDoList'>Add</button>
<button type = 'button' id = 'btnDeleteItem' name = 'deleteList'>Delete All</button>
</div>
</div>
<div id="todoItemsContainer">
</div>
</div>
<script src = './js/app.js'></script>
</body>
</html>
Change your delete function to
let btnDeleteItem = document.getElementById('btnDeleteItem');
btnDeleteItem.onclick = function (){
const items = document.querySelectorAll('.row') // select all todos
items.forEach(el => {
el.remove() // remove each one
})
}
function selectColorStatus(event) {
let target = event.target;
target.classList.toggle('todoTextSelected');
}
function createToDoItem(userInputValue) {
// To-Do Item Container
let todoItem = document.createElement("div");
todoItem.classList.add("row", "flx");
todoItem.onclick = selectColorStatus;
// Clear List
let btnDeleteItem = document.getElementById('btnDeleteItem');
btnDeleteItem.onclick = function () {
const items = document.querySelectorAll('.row')
items.forEach(el => {
el.remove()
})
}
// Inner Text
let todoText = document.createElement('div');
todoText.classList.add('grow');
todoText.innerText = userInputValue;
// Date
let CreateDate = document.createElement('div');
CreateDate.classList.add('date');
let date = new Date();
year = date.getFullYear();
month = date.getMonth();
day = date.getDay();
CreateDate.innerText = 'Created at ' + year + '-' + month + '-' + day;
// Delete Button
let deleteBtn = document.createElement('div');
deleteBtn.classList.add('btnDelete');
deleteBtn.innerText = 'X';
deleteBtn.onclick = function () {
todoItem.remove();
}
todoItem.appendChild(todoText);
todoItem.appendChild(CreateDate)
todoItem.appendChild(deleteBtn);
let todoItemsContainer = document.getElementById('todoItemsContainer');
todoItemsContainer.appendChild(todoItem);
}
// Item Entry and Validation
function ToDoItemHandler() {
let userInput = document.getElementById('toDoEntry');
let userInputValue = userInput.value;
if (userInputValue == '') {
alert('Entry can not be empty!')
} else {
createToDoItem(userInputValue);
userInput.value = '';
}
}
// Add Item Button
let btnAddItem = document.getElementById('btnAddItem');
btnAddItem.onclick = ToDoItemHandler;
<div id = 'container'>
<div id="toDoHeader">
<h1>To-Do List</h1>
<div id = 'toDoContent'>
<input type ='text' id='toDoEntry' name ='toDoEntry' placeholder = 'Add item here'>
<button type ='button' id='btnAddItem' name ='addToDoList'>Add</button>
<button type ='button' id='btnDeleteItem' name ='deleteList'>Delete All</button>
</div>
</div>
<div id="todoItemsContainer">
</div>
</div>
simply do:
// Clear List
let btnDeleteItem = document.getElementById('btnDeleteItem');
btnDeleteItem.onclick = function () {
document.getElementById('todoItemsContainer').innerHTML = ''
}
I have tried all the variations I can find on stackoverflow, but I can still not get the voice to change on SpeechSynthesis
Below is the standalone code that fills a dropdown with all the available voices and allows me to select which voice I want.
Unfortunately this code does not change the voice. Also, before changing the voice. msg.voice is null, even though it has been used to list all the available voices.
Can anyone tell me what is wrong with the code? (console.log(msg.voice); gives a null before being set)
<!doctype html>
<html>
<head>
<SCRIPT>
var msg = new SpeechSynthesisUtterance();
voices = window.speechSynthesis.getVoices();
var numberOfVoices=0;
function Main(){
voiceSelect=document.getElementById("voiceSelect");
setTimeout(getVoicesFunction,2000);
}
function getVoicesFunction(){
msg = new SpeechSynthesisUtterance("hello");
numberOfVoices=0;
speechSynthesis.getVoices().forEach(function(voice) {
var option = document.createElement('option');
option.text = option.value = voice.voiceURI;
voiceSelect.add(option, 0);
numberOfVoices=numberOfVoices+1;
});
voiceSelect.onchange = voiceChange;
}
function voiceChange(){
textToSpeech("this is the old voice");
var selectedOption = this[this.selectedIndex];
selectedVoice = selectedOption.text;
msg = new SpeechSynthesisUtterance();
voices = window.speechSynthesis.getVoices();
msg = new SpeechSynthesisUtterance();
console.log("before change msg.voice");
console.log(msg.voice);
for(i = 0; i < numberOfVoices ; i++) {
if(voices[i].voiceURI === selectedVoice) {
var temp="changing the voice number to "+i;
setTimeout(textToSpeech,2000,temp);
msg.voice = voices[i];
console.log(msg.voice);
var tempVoiceNumber=i;
};
}
setTimeout(textToSpeech,4000,"this is the new voice");
}
function textToSpeech(tspeech){
msg = new SpeechSynthesisUtterance();
msg.text = tspeech;
speechSynthesis.speak(msg);
console.log("speech "+tspeech);
}
</SCRIPT>
</head>
<body onload= "Main()" id= "mainb">
<div id="container">
<select name="Combobox1" size="1" id="voiceSelect">
</select>
</div>
</body>
</html>
IanR, I copied the code and it works for me. I cut out the pitch and rate controls and made the html simpler, but it's basically the same.
If it doesn't work for you are you getting any console errors?
var synth = window.speechSynthesis;
var inputForm = document.querySelector('form');
var inputTxt = document.querySelector('.txt');
var voiceSelect = document.querySelector('select');
/*var pitch = document.querySelector('#pitch');
var pitchValue = document.querySelector('.pitch-value');
var rate = document.querySelector('#rate');
var rateValue = document.querySelector('.rate-value');*/
var voices = [];
function populateVoiceList() {
voices = synth.getVoices();
for (i = 0; i < voices.length; i++) {
var option = document.createElement('option');
option.textContent = voices[i].name + ' (' + voices[i].lang + ')';
if (voices[i].default) {
option.textContent += ' -- DEFAULT';
}
option.setAttribute('data-lang', voices[i].lang);
option.setAttribute('data-name', voices[i].name);
voiceSelect.appendChild(option);
}
}
populateVoiceList();
if (speechSynthesis.onvoiceschanged !== undefined) {
speechSynthesis.onvoiceschanged = populateVoiceList;
}
inputForm.onsubmit = function(event) {
event.preventDefault();
var utterThis = new SpeechSynthesisUtterance(inputTxt.value);
var selectedOption = voiceSelect.selectedOptions[0].getAttribute('data-name');
for (i = 0; i < voices.length; i++) {
if (voices[i].name === selectedOption) {
utterThis.voice = voices[i];
}
}
//utterThis.pitch = pitch.value;
//utterThis.rate = rate.value;
synth.speak(utterThis);
inputTxt.blur();
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>61016951</title>
<script src="61016951.js" defer></script>
</head>
<body>
<div id="div">
<form>
<input type="text" class="txt">
<select></select>
<button type="submit">Play</button>
</form>
</div>
</body>
</html>
Stripping out all the extra bits in your code, here's how you'll need to handle the asynchronous loading on speechSynthesis.getVoices();
if (voiceLoaded()) {
speak();
} else {
speechSynthesis.addEventListener('voiceschanged', speak);
}
function speak() {
const utterance = new SpeechSynthesisUtterance('text');
utterance.voice = getFemaleVoice();
speechSynthesis.speak(utterance);
}
function getFemaleVoice() {
const voiceIndex = 4;
return speechSynthesis.getVoices()[voiceIndex];
}
function voiceLoaded() {
return speechSynthesis.getVoices().length;
}
If the voices array has loaded already then it'll speak the utterance, otherwise this code will add the event listener on the voiceschanged event which will fire once the browser loads the array of voices and then your callback to speak will run.
New to JS here, been struggling with this one for a few hours now.
So I created a to do list with a button that stores objects in an array inside localStorage and also creates dynamic list items with content and delete buttons. Whenever I click the delete button it removes the dynamic list item but doesn't remove it from localStorage. I can't figure out how to assign each button to the specific array index in localStorage.
https://codepen.io/jupiterisland/pen/ooPXWV
var taskList = []; //build array
if(localStorage.taskList){ //call func to recreate li's on refresh
taskList = JSON.parse(localStorage.taskList) || [];
createTasks(taskList)
}
function submitFunc() {
var task = { //build objects
desc: document.getElementsByTagName("textarea")[0].value,
date: document.getElementsByTagName("input")[0].value,
time: document.getElementsByTagName("input")[1].value,
important: document.getElementsByTagName("input")[1].checked
};
if(task.desc && task.date !== ""){
taskList[taskList.length] = task; //put objects inside array
localStorage.taskList = JSON.stringify(taskList); //store array with stringify
newTaskList = JSON.parse(localStorage.taskList); //retrieve array with parse
createTasks(newTaskList)
document.getElementById("error").style.display = "none";
return false; //prevent submit
} else {
document.getElementById("error").style.display = "block";
document.getElementById("error").innerHTML = "Please enter a task description and a date.";
return false;
}
}
function createTasks (newTaskList){
for (i = 0; i < newTaskList.length; i++) { // display objects in list items
var currentTask = newTaskList[i];
var taskIndex = newTaskList.indexOf(currentTask);
newElement();
function newElement() {
var liNode = document.createElement("li");
var titleNode = document.createElement("h3");
var dNode = document.createElement("p");
var tNode = document.createElement("p");
var delNode = document.createElement("button")
liNode.className = "liNode";
titleNode.className = "titleNode";
dNode.className = "dNode";
tNode.className = "tNode";
delNode.className = "delete";
delNode.innerText = "Delete";
var titleText = newTaskList[i].desc;
var dateText = newTaskList[i].date;
var timeText = newTaskList[i].time;
var descNode = document.createTextNode(titleText);
var dateNode = document.createTextNode(dateText);
var timeNode = document.createTextNode(timeText);
titleNode.appendChild(descNode);
dNode.appendChild(dateNode);
tNode.appendChild(timeNode);
liNode.appendChild(titleNode);
liNode.appendChild(dNode);
liNode.appendChild(tNode);
liNode.appendChild(delNode);
document.getElementById("taskBoard").appendChild(liNode);
if (taskBoard.childElementCount > newTaskList.length) { //remove excess divs
for (n = 0; taskBoard.childElementCount - 2; n++) {
taskBoard.removeChild(taskBoard.firstChild);
}
}
function deleteTasks(){
var listItem = this.parentNode;
var ul = listItem.parentNode;
ul.removeChild(listItem);
}
delNode.addEventListener("click", deleteTasks);
}
}
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<body>
<h1>My Task Board</h1>
<div class="container">
<form onsubmit="return submitFunc()">
<div>
<label for="">Task:</label>
<textarea name="name" rows="8" cols="80"placeholder="Please enter your task description"></textarea>
</div>
<div>
<label for="">Deadline:</label>
<input type="date" placeholder="Choose a date">
<input type="time" placeholder="Set time">
</div>
<div>
<label for="">Important:</label>
<input type="checkbox" name="" value="">
</div>
<button type="submit" name="button">Add Task</button>
<div id="error"></div>
</form>
</div>
<div>
<ul id="taskBoard"></ul>
</div>
</body>
</html>
var taskList = []; //build array
if(localStorage.taskList){ //call func to recreate li's on refresh
taskList = JSON.parse(localStorage.taskList) || [];
createTasks(taskList)
}
function fakeGuid() {
function s4() {
return Math.floor((1 + Math.random()) * 0x10000)
.toString(16)
.substring(1);
}
return s4() + s4() + '-' + s4() + '-' + s4() + '-' +
s4() + '-' + s4() + s4() + s4();
}
function submitFunc() {
var task = { //build objects
desc: document.getElementsByTagName("textarea")[0].value,
date: document.getElementsByTagName("input")[0].value,
time: document.getElementsByTagName("input")[1].value,
important: document.getElementsByTagName("input")[1].checked,
id :fakeGuid()
};
if(task.desc && task.date !== ""){
taskList[taskList.length] = task; //put objects inside array
localStorage.taskList = JSON.stringify(taskList); //store array with stringify
newTaskList = JSON.parse(localStorage.taskList); //retrieve array with parse
createTasks(newTaskList)
document.getElementById("error").style.display = "none";
return false; //prevent submit
} else {
document.getElementById("error").style.display = "block";
document.getElementById("error").innerHTML = "Please enter a task description and a date.";
return false;
}
}
function createTasks (newTaskList){
for (i = 0; i < newTaskList.length; i++) { // display objects in list items
newElement(i);
function newElement(currentIndex) {
var liNode = document.createElement("li");
var titleNode = document.createElement("h3");
var dNode = document.createElement("p");
var tNode = document.createElement("p");
var delNode = document.createElement("button")
liNode.className = "liNode";
titleNode.className = "titleNode";
dNode.className = "dNode";
tNode.className = "tNode";
delNode.className = "delete";
delNode.innerText = "Delete";
var titleText = newTaskList[i].desc;
var dateText = newTaskList[i].date;
var timeText = newTaskList[i].time;
var descNode = document.createTextNode(titleText);
var dateNode = document.createTextNode(dateText);
var timeNode = document.createTextNode(timeText);
titleNode.appendChild(descNode);
dNode.appendChild(dateNode);
tNode.appendChild(timeNode);
liNode.appendChild(titleNode);
liNode.appendChild(dNode);
liNode.appendChild(tNode);
liNode.appendChild(delNode);
document.getElementById("taskBoard").appendChild(liNode);
if (taskBoard.childElementCount > newTaskList.length) { //remove excess divs
for (n = 0; taskBoard.childElementCount - 2; n++) {
taskBoard.removeChild(taskBoard.firstChild);
}
}
function deleteTasks(node, currentTask) {
var listItem = node.parentNode;
var ul = listItem.parentNode;
ul.removeChild(listItem);
taskList = taskList.filter(function(t) {
return t.id !== currentTask.id;
});
localStorage.taskList = JSON.stringify(taskList); //store array with stringify
}
var currentTask = newTaskList[currentIndex];
delNode.addEventListener("click", () => deleteTasks(delNode, currentTask));
}
}
}
Don't try to use index to manipulate DOM element. Instead use some kind of unique ID. In this case I created a fake GUID.
Read more on closure. The reason you are not able to pass index down to the function is because the index is bound to another context.
Any reason to stringify JSON for local storage? You can simply store an array.
I have just created random number. My problems is how to get value random in id and how to set price changes automatically every 5 seconds and the fluctuation amplitude less than +/- 5% compared to the current, I don't know use the setinterval function everybody help me
My code Random Price :
function generateRandomNumber(min,max) {
return (Math.random() * (max - min) + min).toFixed(2);
};
document.getElementById('price1').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price2').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price3').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price4').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price5').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price6').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price7').innerHTML = generateRandomNumber(0,99.99);
It took me a while to work around the recursion issues I was running into, before I came up with a better solution.
//<![CDATA[
// external.js
function RandNumMaker(min, max, withinPercent, secondsInterval, decimalPlaces){
this.withinPercent = withinPercent || 5;
this.secondsInterval = secondsInterval || 5;
this.decimalPlaces;
if(decimalPlaces){
this.decimalPlaces = decimalPlaces;
}
var t = this, ia = [];
function rb(mn, mx){
return mx-Math.random()*(mx-mn);
}
var pn = rb(min, max);
function rn(){
var p = 1;
if(Math.floor(Math.random()*2) === 1)p = -1
return p*(Math.floor(Math.random()*t.withinPercent)+1)/100*pn;
}
function rf(){
var r, d = t.decimalPlaces;
pn += rn();
if(pn < min || pn > max){
return rf();
}
r = pn;
if(d)r = (Math.floor(Math.round(Math.pow(10, d+1)*r)/10)/Math.pow(10, d)).toFixed(d);
return r;
}
this.setDiv = function(div){
div.innerHTML = rf(); ia = [];
var iv = setInterval(function(){
div.innerHTML = rf();
}, this.secondsInterval*1000);
ia.push(iv);
return this;
}
this.stop = function(){
for(var i=0,l=ia.length; i<l; i++){
if(ia[i]){
clearInterval(ia[i]);
}
}
ia = [];
return this;
}
}
var doc, bod, C, E, N, old = onload; // for use on other loads
onload = function(){
if(old)old();
doc = document; bod = doc.body;
C = function(tag){
return doc.createElement(tag);
}
E = function(id){
return doc.getElementById(id);
}
N = function(className, inElement){
var ii = inElement || doc;
var cN = ii.getElementsByClassName(className);
if(cN){
return cN;
}
var tn = ii.getElementsByTagName('*');
for(var i=0,e,a=[],l=tn.length; i<l; i++){
e = tn[i];
if(e.className && e.className === className)a.push(e);
}
return a;
}
var sr = new RandNumMaker(0, 99.99), sl = N('slow');
var fr = new RandNumMaker(0, 99.99), fs = N('fast');
sr.decimalPlaces = 2;
fr.secondsInterval = 0.1; fr.withinPercent = 5;
for(var i=0,l=sl.length; i<l; i++){
sr.setDiv(sl[i]);
}
for(var i=0,l=fs.length; i<l; i++){
fr.setDiv(fs[i]);
}
}
//]]>
/* extrnal.js */
html,body{
padding:0; margin:0;
}
body{
background:#000; overflow-y:scroll;
}
.main{
width:940px; background:#fff; padding:20px; margin:0 auto;
}
<!DOCTYPE html>
<html xmlns='http://www.w3.org/1999/xhtml' xml:lang='en' lang='en'>
<head>
<meta http-equiv='content-type' content='text/html;charset=utf-8' />
<meta name='viewport' content='width=device-width' />
<title>test</title>
<link type='text/css' rel='stylesheet' href='external.css' />
<script type='text/javascript' src='external.js'></script>
</head>
<body>
<div class='main'>
<div class='slow'></div>
<div class='slow'></div>
<div class='slow'></div>
<div class='slow'></div>
<div class='slow'></div>
<div class='slow'></div>
<div class='slow'></div>
<hr />
<div class='fast'></div>
<div class='fast'></div>
<div class='fast'></div>
<div class='fast'></div>
</div>
</body>
</html>
Should work now!
After you create a new RandNumMaker(min, max) then you can set randomNumMarkerInstance.decimalPlaces, randomNumMakerInstance.withinPercent and randomNumMakerInstance.secondsInterval using simple assignment. randomNumMakerInstance.setDiv(div) starts it. randomNumMakerInstance.stop() stops it.
I think you can understand this code.
I tried to keep your code.
The key is to use setInterval function.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<script>
function generateRandomNumber(min,max) {
return (Math.random() * (max - min) + min).toFixed(2);
};
function assignData(){
document.getElementById('price1').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price2').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price3').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price4').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price5').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price6').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price7').innerHTML = generateRandomNumber(0,99.99);
setInterval(assignData, 5000); //every 5 seconds
}
</script>
<body onload="assignData()">
<h2 id="price1"></h2>
<h2 id="price2"></h2>
<h2 id="price3"></h2>
<h2 id="price4"></h2>
<h2 id="price5"></h2>
<h2 id="price6"></h2>
<h2 id="price7"></h2>
</body>
</html>
My interpretation of your question: all elements to start with a random value between 0 and 99.99, and then every five seconds one randomly selected element is to be updated, changing its value by a random amount within 5% of its current value. (If you want to update every element every five seconds then change the random selection to be a loop instead.)
For simplicity in the demo snippet (click "Run code snippet" to see it work), I've used a group of <li> elements which I select with .querySelectorAll("li"), but if you really want to do it using element IDs you could say .querySelectorAll("#price1,#price2,#price3,#price4,#price5,#price6,#price7").
function generateRandomNumber(min,max) {
return (Math.random() * (max - min) + min).toFixed(2);
}
// get list of elements:
var elements = document.querySelectorAll("li");
// populate all elements initially:
[].forEach.call(elements, function(el) {
el.innerHTML = generateRandomNumber(0,99.99);
});
// update an element at random every second:
setInterval(function update() {
var element = elements[Math.floor(Math.random() * elements.length)];
var currentVal = +element.innerHTML;
element.innerHTML = generateRandomNumber(currentVal * 0.95, currentVal * 1.05);
}, 1000);
<ul>
<li></li><li></li><li></li><li></li><li></li><li></li><li></li>
</ul>
Note that five second intervals seemed too slow for a demo, so I've used one second (1000ms) here.
Further reading:
.querySelectorAll()
Array .forEach() method
Function.prorotype.call()
Math.floor()
unary plus operator
Hope this will help.
<body>
<p id="price1"></p>
<p id="price2"></p>
<p id="price3"></p>
<p id="price4"></p>
<p id="price5"></p>
<p id="price6"></p>
<p id="price7"></p>
</body>
<script>
//set initial random number for the elements
document.getElementById('price1').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price2').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price3').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price4').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price5').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price6').innerHTML = generateRandomNumber(0,99.99);
document.getElementById('price7').innerHTML = generateRandomNumber(0,99.99);
//set random number to elements with fluctuation +/- 5%
setRandomToElements()
function generateRandomNumber(min,max) {
return (Math.random() * (max - min) + min).toFixed(2);
};
function setRandomToElements(){
//get current prices
var currentPrice1 = parseInt(document.getElementById('price1').innerHTML);
var currentPrice2 = parseInt(document.getElementById('price2').innerHTML);
var currentPrice3 = parseInt(document.getElementById('price3').innerHTML);
var currentPrice4 = parseInt(document.getElementById('price4').innerHTML);
var currentPrice5 = parseInt(document.getElementById('price5').innerHTML);
var currentPrice6 = parseInt(document.getElementById('price6').innerHTML);
var currentPrice7 = parseInt(document.getElementById('price7').innerHTML);
var fluctuation = 0.05;//5%
//random new numbers +/-5% current price
document.getElementById('price1').innerHTML = generateRandomNumber(currentPrice1-(currentPrice1*fluctuation), currentPrice1+(currentPrice1*fluctuation));
document.getElementById('price2').innerHTML = generateRandomNumber(currentPrice2-(currentPrice2*fluctuation), currentPrice2+(currentPrice2*fluctuation));
document.getElementById('price3').innerHTML = generateRandomNumber(currentPrice3-(currentPrice3*fluctuation), currentPrice3+(currentPrice3*fluctuation));
document.getElementById('price4').innerHTML = generateRandomNumber(currentPrice4-(currentPrice4*fluctuation), currentPrice4+(currentPrice4*fluctuation));
document.getElementById('price5').innerHTML = generateRandomNumber(currentPrice5-(currentPrice5*fluctuation), currentPrice5+(currentPrice5*fluctuation));
document.getElementById('price6').innerHTML = generateRandomNumber(currentPrice6-(currentPrice6*fluctuation), currentPrice6+(currentPrice6*fluctuation));
document.getElementById('price7').innerHTML = generateRandomNumber(currentPrice7-(currentPrice7*fluctuation), currentPrice7+(currentPrice7*fluctuation));
setInterval(setRandomToElements, 5000);
}
</script>
Fiddle