Web Front-end
JS Tutorial
How to store JavaScript functions in a queue and execute them sequentially?
How to store JavaScript functions in a queue and execute them sequentially?
Sometimes, a developer may need to store a function in a queue and execute it in the order it is stored in the queue. In JavaScript, we can use arrays to create a queue. We can use the push() method of the array to queue the function, and use the shift() method to dequeue the function from the queue.
Below, we will see examples of storing JavaScript functions in the queue and executing them in the queue order.
Syntax
Users can store JavaScript functions in the queue according to the following syntax and execute them in sequence.
while (queue.length > 0) {
queue[0]();
queue.shift();
}
We use the while loop in the above syntax to traverse the queue. We execute the first function in the queue and then remove that function from the queue.
Example
In the following example, we create a variable named queue and initialize it with an empty array to make it a queue.
After that, we created three different functions and used the push() method of the array to add all functions into the queue. Whenever users press the button, it calls the executeFunctions() function. In the executeFunctions() function, we use the while loop to deque the function from the queue. In every iteration of the loop, we execute the first function from the array and use the array.shift() method to remove the first element from the array.
<html>
<body>
<h3 id="Using-the-array-to-add-functions-in-Queue-and-execute-functions-in-particular-order">Using the array to add functions in Queue and execute functions in particular order</h3>
<div id = "content"> </div></br>
<button onclick = "executeFunctions()"> Execute function in queue order </button>
<script>
let content = document.getElementById("content");
// execute the functions in the order they are added to the queue
var queue = [];
function executeFunctions() {
while (queue.length > 0) {
queue[0]();
queue.shift();
}
}
function function1() {
content.innerHTML += "Function 1 executed <br>";
}
function function2() {
content.innerHTML += "Function 2 executed <br>";
}
function function3() {
content.innerHTML += "Function 3 executed <br>";
}
queue.push(function1);
queue.push(function2);
queue.push(function3);
</script>
</body>
</html>
Example
In the following example, we create an array to use as a queue, just like the first example. After that, we add the sum(), sub(), mul() and div() functions to the queue.
In the executeFunctions() function, we use a for loop to call all functions in queue order. In addition, we also used the call() method to call a function from the queue.
<html>
<body>
<h3 id="Using-the-array-to-add-functions-in-Queue-and-execute-functions-in-particular-order">Using the array to add functions in Queue and execute functions in particular order</h3>
<div id = "content"> </div> </br>
<button onclick = "executeFunctions()"> Execute function in queue order </button>
<script>
let content = document.getElementById("content");
// execute the functions in the order they are added to the queue
var queue = [];
function executeFunctions() {
for (let i = 0; i < queue.length; i++) {
queue[i].call();
}
}
let a = 10;
let b = 5;
function sum() {
content.innerHTML += "Sum of " + a + " and " + b + " is " + (a + b);
}
function sub() {
content.innerHTML += "<br>Subtraction of " + a + " and " + b + " is " + (a - b);
}
function mul() {
content.innerHTML += "<br>Multiplication of " + a + " and " + b + " is " + (a * b);
}
function div() {
content.innerHTML += "<br>Division of " + a + " and " + b + " is " + (a / b);
}
queue.push(sum);
queue.push(sub);
queue.push(mul);
queue.push(div);
</script>
</body>
</html>
Users learned to store functions in a queue and execute them in queue order. In JavaScript, there is no built-in queue data structure, but we can use arrays as queues.
In the first example, we have used the shift() method to deque the queue. In the second example, we have used the for loop to execute the functions in order.
The above is the detailed content of How to store JavaScript functions in a queue and execute them sequentially?. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
AI Hentai Generator
Generate AI Hentai for free.
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
Replace String Characters in JavaScript
Mar 11, 2025 am 12:07 AM
Detailed explanation of JavaScript string replacement method and FAQ This article will explore two ways to replace string characters in JavaScript: internal JavaScript code and internal HTML for web pages. Replace string inside JavaScript code The most direct way is to use the replace() method: str = str.replace("find","replace"); This method replaces only the first match. To replace all matches, use a regular expression and add the global flag g: str = str.replace(/fi
jQuery Check if Date is Valid
Mar 01, 2025 am 08:51 AM
Simple JavaScript functions are used to check if a date is valid. function isValidDate(s) { var bits = s.split('/'); var d = new Date(bits[2] '/' bits[1] '/' bits[0]); return !!(d && (d.getMonth() 1) == bits[1] && d.getDate() == Number(bits[0])); } //test var
jQuery get element padding/margin
Mar 01, 2025 am 08:53 AM
This article discusses how to use jQuery to obtain and set the inner margin and margin values of DOM elements, especially the specific locations of the outer margin and inner margins of the element. While it is possible to set the inner and outer margins of an element using CSS, getting accurate values can be tricky. // set up $("div.header").css("margin","10px"); $("div.header").css("padding","10px"); You might think this code is
10 jQuery Accordions Tabs
Mar 01, 2025 am 01:34 AM
This article explores ten exceptional jQuery tabs and accordions. The key difference between tabs and accordions lies in how their content panels are displayed and hidden. Let's delve into these ten examples. Related articles: 10 jQuery Tab Plugins
10 Worth Checking Out jQuery Plugins
Mar 01, 2025 am 01:29 AM
Discover ten exceptional jQuery plugins to elevate your website's dynamism and visual appeal! This curated collection offers diverse functionalities, from image animation to interactive galleries. Let's explore these powerful tools: Related Posts: 1
HTTP Debugging with Node and http-console
Mar 01, 2025 am 01:37 AM
http-console is a Node module that gives you a command-line interface for executing HTTP commands. It’s great for debugging and seeing exactly what is going on with your HTTP requests, regardless of whether they’re made against a web server, web serv
Custom Google Search API Setup Tutorial
Mar 04, 2025 am 01:06 AM
This tutorial shows you how to integrate a custom Google Search API into your blog or website, offering a more refined search experience than standard WordPress theme search functions. It's surprisingly easy! You'll be able to restrict searches to y
jquery add scrollbar to div
Mar 01, 2025 am 01:30 AM
The following jQuery code snippet can be used to add scrollbars when the div content exceeds the container element area. (No demonstration, please copy it directly to Firebug) //D = document //W = window //$ = jQuery var contentArea = $(this), wintop = contentArea.scrollTop(), docheight = $(D).height(), winheight = $(W).height(), divheight = $('#c
