I wanted to call a function defined in a first.js file in second.js file. Both files are defined in an HTML file like:
<script type="text/javascript" src="first.js"></script>
<script type="text/javascript" src="second.js"></script>
I want to call fn1() defined in first.js in second.js. From my searches answers were if first.js is defined first it is possible, but from my tests I haven't found any way to do that.
Here is my code:
second.js
document.getElementById("btn").onclick = function() {
fn1();
}
first.js
function fn1() {
alert("external fn clicked");
}
A function cannot be called unless it was defined in the same file or one loaded before the attempt to call it.
A function cannot be called unless it is in the same or greater scope then the one trying to call it.
You declare function fn1 in first.js, and then in second you can just have fn1();
1.js:
function fn1 () {
alert();
}
2.js:
fn1();
index.html :
<script type="text/javascript" src="1.js"></script>
<script type="text/javascript" src="2.js"></script>
You could consider using the es6 import export syntax. In file 1;
export function f1() {...}
And then in file 2;
import { f1 } from "./file1.js";
f1();
Please note that this only works if you're using <script src="./file2.js" type="module">
You will not need two script tags if you do it this way. You simply need the main script, and you can import all your other stuff there.
1st JS:
function fn(){
alert("Hello! Uncle Namaste...Chalo Kaaam ki Baat p Aate h...");
}
2nd JS:
$.getscript("url or name of 1st Js File",function(){
fn();
});
You can make the function a global variable in first.js
and have a look at closure and do not put it in document.ready put it outside
you can use ajax too
$.ajax({
url: "url to script",
dataType: "script",
success: success
});
same way you can use jquery getScript
$.getScript( "ajax/test.js" )
.done(function( script, textStatus ) {
console.log( textStatus );
})
.fail(function( jqxhr, settings, exception ) {
$( "div.log" ).text( "Triggered ajaxError handler." );
});
declare function in global scope with window
first.js
window.fn1 = function fn1() {
alert("external fn clicked");
}
second.js
document.getElementById("btn").onclick = function() {
fn1();
}
include like this
<script type="text/javascript" src="first.js"></script>
<script type="text/javascript" src="second.js"></script>
use "var" while creating a function, then you can access that from another file. make sure both files are well connected to your project and can access each other.
file_1.js
var firstLetterUppercase = function(str) {
str = str.toLowerCase().replace(/\b[a-z]/g, function(letter) {
return letter.toUpperCase();
});
return str;
}
accessing this function/variable from file_2.js file
firstLetterUppercase("gobinda");
output => Gobinda
It should work like this:
1.js
function fn1() {
document.getElementById("result").innerHTML += "fn1 gets called";
}
2.js
function clickedTheButton() {
fn1();
}
index.html
<html>
<head>
</head>
<body>
<button onclick="clickedTheButton()">Click me</button>
<script type="text/javascript" src="1.js"></script>
<script type="text/javascript" src="2.js"></script>
</body>
</html>
output
Try this CodePen snippet: link .
Please note this only works if the
<script>
tags are in the body and NOT in the head.
So
<head>
...
<script type="text/javascript" src="first.js"></script>
<script type="text/javascript" src="second.js"></script>
</head>
=> unknown function fn1()
Fails and
<body>
...
<script type="text/javascript" src="first.js"></script>
<script type="text/javascript" src="second.js"></script>
</body>
works.
This is actually coming very late, but I thought I should share,
in index.html
<script type="text/javascript" src="1.js"></script>
<script type="text/javascript" src="2.js"></script>
in 1.js
fn1 = function() {
alert("external fn clicked");
}
in 2.js
fn1()
Use cache if your server allows it to improve speed.
var extern =(url)=> { // load extern javascript
let scr = $.extend({}, {
dataType: 'script',
cache: true,
url: url
});
return $.ajax(scr);
}
function ext(file, func) {
extern(file).done(func); // calls a function from an extern javascript file
}
And then use it like this:
ext('somefile.js',()=>
myFunc(args)
);
Optionally, make a prototype of it to have it more flexible. So that you don't have to define the file every time, if you call a function or if you want to fetch code from multiple files.
first.js
function first() { alert("first"); }
Second.js
var imported = document.createElement("script");
imported.src = "other js/first.js"; //saved in "other js" folder
document.getElementsByTagName("head")[0].appendChild(imported);
function second() { alert("Second");}
index.html
<HTML>
<HEAD>
<SCRIPT SRC="second.js"></SCRIPT>
</HEAD>
<BODY>
method in second js<br/>
method in firstjs ("included" by the first)
</BODY>
</HTML>
window.onload = function(){
document.getElementById("btn").onclick = function(){
fn1();
}
// this should work, It calls when all js files loaded, No matter what position you have written
});
// module.js
export function hello() {
return "Hello";
}
// main.js
import {hello} from 'module'; // or './module'
let val = hello(); // val is "Hello";
reference from https://hype.codes/how-include-js-file-another-js-file
My idea is let two JavaScript call function through DOM.
The way to do it is simple ...
We just need to define hidden js_ipc html tag.
After the callee register click from the hidden js_ipc tag, then
The caller can dispatch the click event to trigger callee.
And the argument is save in the event that you want to pass.
When we need to use above way ?
Sometime, the two javascript code is very complicated to integrate and so many async code there. And different code use different framework but you still need to have a simple way to integrate them together.
So, in that case, it is not easy to do it.
In my project's implementation, I meet this case and it is very complicated to integrate. And finally I found out that we can let two javascript call each other through DOM.
I demonstrate this way in this git code. you can get it through this way. (Or read it from https://github.com/milochen0418/javascript-ipc-demo)
git clone https://github.com/milochen0418/javascript-ipc-demo
cd javascript-ipc-demo
git checkout 5f75d44530b4145ca2b06105c6aac28b764f066e
Anywhere, Here, I try to explain by the following simple case. I hope that this way can help you to integrate two different javascript code easier than before there is no any JavaScript library to support communication between two javascript file that made by different team.
<html>
<head>
<link rel="stylesheet" type="text/css" href="css/style.css" />
</head>
<body>
<div id="js_ipc" style="display:none;"></div>
<div id="test_btn" class="btn">
<a><p>click to test</p></a>
</div>
</body>
<script src="js/callee.js"></script>
<script src="js/caller.js"></script>
</html>
And the code
css/style.css
.btn {
background-color:grey;
cursor:pointer;
display:inline-block;
}
js/caller.js
function caller_add_of_ipc(num1, num2) {
var e = new Event("click");
e.arguments = arguments;
document.getElementById("js_ipc").dispatchEvent(e);
}
document.getElementById("test_btn").addEventListener('click', function(e) {
console.log("click to invoke caller of IPC");
caller_add_of_ipc(33, 22);
});
js/callee.js
document.getElementById("js_ipc").addEventListener('click', (e)=>{
callee_add_of_ipc(e.arguments);
});
function callee_add_of_ipc(arguments) {
let num1 = arguments[0];
let num2 = arguments[1];
console.log("This is callee of IPC -- inner-communication process");
console.log( "num1 + num2 = " + (num1 + num2));
}
better late than never
(function (window) {const helper = { fetchApi: function () { return "oke"}
if (typeof define === 'function' && define.amd) {
define(function () { return helper; });
}
else if (typeof module === 'object' && module.exports) {
module.exports = helper;
}
else {
window.helper = helper;
}
}(window))
index html
<script src="helper.js"></script>
<script src="test.js"></script>
in test.js file
helper.fetchApi()
I have had same problem. I have had defined functions inside jquery document ready function.
$(document).ready(function() {
function xyz()
{
//some code
}
});
And this function xyz() I have called in another file. This doesn't working :) You have to defined function above document ready.
TLDR: Load Global Function Files first, Then Load Event Handlers
Whenever you are accessing an element within a JS file or <script> block, it is essential to check to make sure that element exists, i.e., jQuery's $(document).ready() or plain JS's document.addEventListener('DOMContentLoaded', function(event)....
However, the accepted solution does NOT work in the event that you add an event listener for the DOMContentLoaded, which you can easily observe from the comments.
Procedure for Loading Global Function Files First
The solution is as follows:
Separate the logic of your JS script files so that each file only contains event listeners or global, independent functions.
Load the JS script files with the global, independent functions first.
Load the JS script files with event listeners second. Unlike the other previous files, make sure to wrap your code in document.addEventListener('DOMContentLoaded', function(event) {...}). or document.Ready().
Is there a difference between lauch js functions from same JS file where they declared after page load, or in html template? When both signed into $(document).ready(function () {...}).
I assume that no, but I ran into a problem when replace my ExampleService.init() function from template to separate JS file.
For example i have that construction:
common.js
var ExampleService= {
catalogSpinner: '',
init: function() {
this.initEvents();
},
initEvents: function() {
var self = this;
$('.example-button').on('click', function() {
//do some logic, append spinner...
self.removeSpinner();
});
},
removeSpinner: function() {
$(this.catalogSpinner).fadeOut('slow', function() {
$(this).remove().css({display: 'block'});
});
}
}
index.html
<script src="js/common.js"></script>
<script>
$(document).ready(function () {
ExampleService.catalogSpinner = '<div class="spinner"></div>'; // css3 animation
ExampleService.init();
});
</script>
That way all works perfect, my catalogSpinner overriden from template, and i can use them like DOM element.
But! if i move ExampleService.init(); to common.js file, like that:
common.js
var ExampleService= {
...
// all the same...
...
};
$(document).ready(function () {
'use strict';
ExampleService.init();
});
index.html
<script src="js/common.js"></script>
<script>
$(document).ready(function () {
ExampleService.catalogSpinner = '<div class="spinner"></div>';
});
</script>
That way it wouldn't work. And throw console error Uncaught TypeError: this.catalogSpinner.fadeOut is not a function
Why it's happens? After all in both cases init functions starts only after full page load, and no matters that i override my variable after starting base functions. What im doing wrong?
About orders in which inits will executed. How i understand its no matter. Cause in any case, second document.ready from template file, always ovverride empty catalogSpinner variable from JS file, before click event happens
It's almost certainly a timing issue. What guarantee do you have that $(document).ready in common.js will fire after the same event handler in your html file (which is what needs to happen according to your implementation)?
Or, you need to make sure that when it occurs in common.js, that code can somehow retrieve the catalogSpinner value.
Also, catalogSpinner needs to be a valid jQuery object, not a string.
It will and it does work in both the cases. To use jQuery methods over DOM elements, you must have valid jQuery selectors which will return objects binded with jQuery methods.
Try this:
case 1:
common.js
var ExampleService= {
catalogSpinner: '',
init: function() {
this.initEvents();
},
initEvents: function() {
var self = this;
$('.example-button').on('click', function() {
//do some logic, append spinner...
self.removeSpinner();
});
},
removeSpinner: function() {
this.catalogSpinner.fadeOut('slow', function() {
$(this).remove().css({display: 'block'});
});
}
};
index.html
<!doctype html>
<html>
<head>
<script src="jquery.min.js"></script>
<script src="common.js"></script>
<style>
</style>
</head>
<body>
<div class="spinner">Spinner</div>
<button type="button" class="example-button">Remove</button>
<script type="text/javascript">
$(document).ready(function () {
ExampleService.catalogSpinner = $('.spinner');
ExampleService.init();
});
</script>
</body>
</html>
case 2:
common.js
var ExampleService = {
catalogSpinner: '',
init: function () {
this.initEvents();
},
initEvents: function () {
var self = this;
$('.example-button').on('click', function () {
//do some logic, append spinner...
self.removeSpinner();
});
},
removeSpinner: function () {
this.catalogSpinner.fadeOut('slow', function () {
$(this).remove().css({display: 'block'});
});
}
};
$(document).ready(function () {
'use strict';
ExampleService.init();
});
index.html
<!doctype html>
<html>
<head>
<script src="jquery.min.js"></script>
<script src="common.js"></script>
<style>
</style>
</head>
<body>
<div class="spinner">Spinner</div>
<button type="button" class="example-button">Remove</button>
<script type="text/javascript">
$(document).ready(function () {
ExampleService.catalogSpinner = $('.spinner');
});
</script>
</body>
</html>
I've got a problem and can't figure it out and would be glad if anyone of you could help me. So basically what I am trying to do is to put multiple window.onload events in a seperate file which starts my scripts. To get clear what I mean her is my situation:
Let's say I got these files:
index.html
<html>
<head>
<link rel="stylesheet" href="style.css" type="text/css">
<script type="text/javascript" src="kalkevent.js"></script>
<script type="text/javascript" src="reckevent.js"></script>
<script type="text/javascript" src="winonload.js"></script>
</head>
<body>
<div id="topColumn">
...
</div>
<div id="bottomColumn">
...
</div>
</body>
</html>
kalk.js
function kalkInit() {
Array.prototype.slice.call(document.forms[0].elements).forEach(function(element) {
...
});
};
reck.js
function reckInit() {
...
};
So I want to load kalkInit and reckInit on window.onload . This should be handled in a separate file. What I already tried is:
winonload.js
function addLoadEvent(func) {
var oldonload = window.onload;
if (typeof window.onload != 'function') {
window.onload = func;
} else {
window.onload = function() {
if (oldonload) {
oldonload();
}
func();
};
}
};
addLoadEvent(kalkInit);
addLoadEvent(reckInit);
But it's not working at all. So my question is if it possible what I am trying to do or not. And if it is could someone pls help me out? :)
You can consider using jQuery..
In your winonload.js you need only:
$(window).on("load", kalkInit);
$(window).on("load", reckInit);
Maybe you have to call your onloadfunction:
<body onload="addLoadEvent();">
If I have this code in a file called custom.js:
var kennel = function(){this._init();};
kennel.prototype = {
_init: function() {
this.setListeners();
},
setListeners: function(){
...
},
getCats: function(){
alert("Get cats");
}
};
How do I call getCats() from some arbitrary html file?
First of all you would include the javascript by using the <script> tag, generally in the <head>, then after that you can create another <script> tag which you can place your own javascript code in that is specific to the page, and which uses the functionality made available by the included file. For example:
<head>
<script type="text/javascript" src="path/to/custom.js"></script>
<script type="text/javascript">
var myKennel = new kennel();
myKennel.getCats(); // alerts "Get cats"
</script>
</head>
Also, the code you have posted has nothing to do with jQuery - it is plain old, vanilla javascript.
This should be enough:
<script>
var k = new kennel();
k.getCats();
</script>
Here's a sample of it working: http://jsfiddle.net/NHaBb/
Hi i have a problem with my js code. So, i include in 'head' in my site, script
var Engine;
jQuery
(
function($)
{
Engine =
{
utils :
{
site : function(id)
{
$('#content').html('<strong>Please wait..</strong>').load('engine.php',{'site':id},function()
{
os = {adres:'drugi'};
history.pushState(os,'s',ts);
}
);
},
topnav : function()
{
$('div li').bind('click',function()
{
Engine.utils.site($(this).attr('rel'));
unbind('click',false);
}
);
}
}
};
Engine.utils.topnav();
}
);
Now i want call included script in index.php
<script language="JavaScript" type="text/javascript">
Engine.utils.site(1);
</script>
And here is a problem above code doesn't works.
But if i click on any 'li' element Engine.utils.site work's correctly.
Please help me i try fix it a few days.
Sory for my bad english
Have you tried putting the call in a ready function?
<script language="JavaScript" type="text/javascript">
$(function() {
Engine.utils.site(1);
});
</script>
This happens because of closure. Your object Engine is not visible outside anonymous function