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JavaScript JavaScript and the DOM (Retiring) Making Changes to the DOM Getting and Setting Text with textContent and innerHTML

how to know which way round to write code inside a button.addEventListener?

button.addEventListener("click", function(){
p.textContent = input.value;
});

The above is correct, but at first i wrote :

button.addEventListener("click", function(){
input.value = p.textContent;
});
Although it didnt work how do i know which way round to write apart from trial and error? Is it best to think of it this way, start with the item that you want to change?

1 Answer

Cameron Childres
Cameron Childres
11,817 Points

Hi Jason,

The left side receives the value, the right side gives the value. Consider what would be logged in this situation:

let a = 1;
let b = 2;
a = b;
console.log(a);
console.log(b);

"Start with the item that you want to change" is a fair way to think of it. In your example you want p.textContent to receive the value from input.value, so p.textContent goes on the left and input.value goes on the right.