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");
}
This question is related to
javascript
html
The answer is
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
});
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();
});
Hope This Helps... Happy Coding.
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));
}
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.
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." );
});
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()
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>
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.
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>
<a href="javascript:second()">method in second js</a><br/>
<a href="javascript:first()">method in firstjs ("included" by the first)</a>
</BODY>
</HTML>
// 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
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.
This code should work. If it doesn't, check the sources in your debugger tool (Press F12 or Ctrl+Shift+I in Google Chrome). If you can't find the fn1() function there then, press Ctrl+F5, to fully reload the site (Ctrl+R or F5 isn't enough). After reloading the page, it should work.
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.
use "var" while creating 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 form file_2.js file
firstLetterUppercase("gobinda");
output => Gobinda
hope this will help somebody, happy coding !!!
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 .
Source: Stackoverflow.com