I have a problem I would say stupid with html and javascript, a simple function that should make me visible and invisible a div crashes the html making it empty!
<button onclick="open()">Modifica</button>
js:
var x = document.getElementById ("joseph");
if (x.hidden == false) {
x.hidden = true;
} else {
x.hidden = false;
}
You don't have to write pre-defined methods. It works same for all other tech stacks such as Mysql, PHP, etc.
Recommend using opens, not open if you insist to use the open word.
<button onclick="opens()">Modifica</button>
You've hit a variation of this problem.
When searching for a variable named open the browser finds document.open before it finds your open function.
document.open opens a new document for writing (with document.write) which erases the existing document.
window.open is also predefined, so making a new global function with that name is not advised.
As with the linked question: Use addEventListener instead of onclick attributes.