How can I get the ID of an HTML element in a JavaScript function without passing any parameters?

Question

How can I get the ID of an HTML element in a JavaScript function without passing any parameters?

I have a HTML element:

<input type="text" id="exampleInput" value="0" onkeypress="exampleFunction()">

From JavaScript, I would like to change the value of the HTML element.

function exampleFunction() {
    
}

Is it possible to achieve this without passing the ID as a parameter?

Answer 1

You can pass this to your function like this:

 function exampleFunction(e) { console.log(e); // element console.log(e.id); // id e.value = 'new value'; // change value }

 <input type="text" id="exampleInput" value="0" onkeypress="exampleFunction(this)">

Or, better yet, use addEventListener instead:

 document.getElementById('exampleInput').addEventListener('keypress', function (e) { console.log(e.target); // element console.log(e.target.id); // id e.target.value = 'new value'; // change value });

 <input type="text" id="exampleInput" value="0">

Answer 2

You can pass the element into the function as this .

 function exampleFunction(element) { console.log(element.value); }

 <input type="text" id="exampleInput" value="0" onkeypress="exampleFunction(this)">