Why does this JavaScript doesnt script the html div. Function after the "click" is defined too

Question

document.getElementById("display").addEventListener("click", display);
document.getElementById("searchnumber").addEventListener("click",searchnumber);
document.getElementById("searchname").addEventListener("click",searchname);
document.getElementById("quit").addEventListener("click",quit);

Answer 1

Maybe because of script is starts before all elements are loaded?
Put your code in <script></script> at the bottom of body.
Or put code in
window.onload = function(){/*put here*/}
and check how it works.

Answer 2

ok Works fine if i put the Script into the End of Body of html. is There a Way to seperate it into the js Part of coding? thank u for ur answer. ok Moment i will try the "onload"