Is it possible for a button to be assigned to a variable upon creation, but encounter an error when trying to

const button:Element = document.createElement("button");//This works fine
const button:HTMLButtonElement = document.createElement("button");//This works too

const button2:Element = document.getElementsByTagName("button");//Why does this give an error?
const button3:HTMLButtonElement = document.getElementsByTagName("button");//And why does this one also give an error?

After using VS Code, I noticed that the interfaces missing classlist and autofocus property respectively. But then why is it acceptable when creating the element?

  • How can I assign a variable to an existing element and add an event listener to it?

Answer №1

This issue is not acceptable as both

let button2:Element = document.getElementsByTagName("button");
let button3:HTMLButtonElement = document.getElementsByTagName("button");

return an array instead of a single element. To rectify this, you can simply select the first item from the array:

let button2:Element = document.getElementsByTagName("button")[0];
let button3:HTMLButtonElement = document.getElementsByTagName("button")[0];

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