Answers for "set onclick attribute in js"

set onclick javascript

<button id="myBtn">Try it</button>
<p id="demo"></p>

<script>
document.getElementById("myBtn").onclick=function(){displayDate()};

function displayDate()
{
    document.getElementById("demo").innerHTML=Date();
}
</script>

change onclick attribute with javascrip

document.getElementById(id).setAttribute('onclick','myFunction()')