开发者

How to call multiple JavaScript functions in onclick event?

Is there any way to use the onclick html attribute to call more than one开发者_运维技巧 JavaScript function?


onclick="doSomething();doSomethingElse();"

But really, you're better off not using onclick at all and attaching the event handler to the DOM node through your Javascript code. This is known as unobtrusive javascript.


A link with 1 function defined

<a href="#" onclick="someFunc()">Click me To fire some functions</a>

Firing multiple functions from someFunc()

function someFunc() {
    showAlert();
    validate();
    anotherFunction();
    YetAnotherFunction();
}


This is the code required if you're using only JavaScript and not jQuery

var el = document.getElementById("id");
el.addEventListener("click", function(){alert("click1 triggered")}, false);
el.addEventListener("click", function(){alert("click2 triggered")}, false);


I would use the element.addEventListener method to link it to a function. From that function you can call multiple functions.

The advantage I see in binding an event to a single function and then calling multiple functions is that you can perform some error checking, have some if else statements so that some functions only get called if certain criteria are met.


Sure, simply bind multiple listeners to it.

Short cutting with jQuery

$("#id").bind("click", function() {
  alert("Event 1");
});
$(".foo").bind("click", function() {
  alert("Foo class");
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="foo" id="id">Click</div>


ES6 React

<MenuItem
  onClick={() => {
    this.props.toggleTheme();
    this.handleMenuClose();
  }}
>


var btn = document.querySelector('#twofuns');
btn.addEventListener('click',method1);
btn.addEventListener('click',method2);
function method2(){
  console.log("Method 2");
}
function method1(){
  console.log("Method 1");
}
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>Pramod Kharade-Javascript</title>
</head>
<body>
<button id="twofuns">Click Me!</button>
</body>
</html>

You can achieve/call one event with one or more methods.


You can add multiple only by code even if you have the second onclick atribute in the html it gets ignored, and click2 triggered never gets printed, you could add one on action the mousedown but that is just an workaround.

So the best to do is add them by code as in:

var element = document.getElementById("multiple_onclicks");
element.addEventListener("click", function(){console.log("click3 triggered")}, false);
element.addEventListener("click", function(){console.log("click4 triggered")}, false);
<button id="multiple_onclicks" onclick='console.log("click1 triggered");' onclick='console.log("click2 triggered");' onmousedown='console.log("click mousedown triggered");'  > Click me</button>

You need to take care as the events can pile up, and if you would add many events you can loose count of the order they are ran.


One addition, for maintainable JavaScript is using a named function.

This is the example of the anonymous function:

var el = document.getElementById('id');

// example using an anonymous function (not recommended):
el.addEventListener('click', function() { alert('hello world'); });
el.addEventListener('click', function() { alert('another event') });

But imagine you have a couple of them attached to that same element and want to remove one of them. It is not possible to remove a single anonymous function from that event listener.

Instead, you can use named functions:

var el = document.getElementById('id');

// create named functions:
function alertFirst() { alert('hello world'); };
function alertSecond() { alert('hello world'); };

// assign functions to the event listeners (recommended):
el.addEventListener('click', alertFirst);
el.addEventListener('click', alertSecond);

// then you could remove either one of the functions using:
el.removeEventListener('click', alertFirst);

This also keeps your code a lot easier to read and maintain. Especially if your function is larger.


React Functional components

             <Button
                onClick={() => {
                  cancelAppointment();
                  handlerModal();
                }}
             >
                Cancel
             </Button>


 const callDouble = () =>{
    increaseHandler();
    addToBasket();
}                
<button onClick={callDouble} > Click </button>

It's worked for me, you can call multiple functions in a single function. then call that single function.


Here is another answer that attaches the click event to the DOM node in a .js file. It has a function, callAll, that is used to call each function:

const btn = document.querySelector('.btn');

const callAll = 
  (...fns) =>
  (...args) =>
    fns.forEach(fn => fn?.(...args));

function logHello() {
  console.log('hello');
}

function logBye() {
  console.log('bye');
}


btn.addEventListener('click', 
  callAll(logHello, logBye)
); 
<button type="button" class="btn">
  Click me
</button>


You can compose all the functions into one and call them.Libraries like Ramdajs has a function to compose multiple functions into one.

<a href="#" onclick="R.compose(fn1,fn2,fn3)()">Click me To fire some functions</a>

or you can put the composition as a seperate function in js file and call it

const newFunction = R.compose(fn1,fn2,fn3);


<a href="#" onclick="newFunction()">Click me To fire some functions</a>


This is alternative of brad anser - you can use comma as follows

onclick="funA(), funB(), ..."

however is better to NOT use this approach - for small projects you can use onclick only in case of one function calling (more: updated unobtrusive javascript).

function funA() {
  console.log('A');
}

function funB(clickedElement) {
  console.log('B: ' + clickedElement.innerText);
}

function funC(cilckEvent) {
  console.log('C: ' +  cilckEvent.timeStamp);
}
div {cursor:pointer}
<div onclick="funA(), funB(this), funC(event)">Click me</div>

0

上一篇:

下一篇:

精彩评论

暂无评论...
验证码 换一张
取 消

最新问答

问答排行榜